Falling on purpose?

Dehydration is one of the most common causes of dizziness in older adults. For whatever reason, the normal awareness of thirst isn't very strong, so they wait too long to drink anything and drink too little even then. Make sure that your mom starts drinking a few extra glasses of water every day.
Also, at least temporarily, put a bedside commode right next to the bed so that she won't have to walk during the night. (If you also buy the plastic commode liners, it's really not very much trouble to empty it.)
Were her medicines recently changed? If they were, then it's entirely possible that unexpected side effects or interactions are just now coming to light. One of them may be dizziness. Do a little research on your own and see if any of the medicines she is taking might be causing it. And don't rely simply on what you're told! For instance, my late fiance had terrible balance problems. I suspected that the Flomax he took for his prostate might be the culprit, but both the pharmacist and nurse insisted that his lightheadedness and balance problems couldn't be caused by it. Well, the prescription fact sheet itself disagreed: It said that dizziness was a "common" side effect!
Be a detective. Do your research. It is probably something very simple. I'm pretty sure your mom isn't falling on purpose.

Imho, she may not have regained all of her strength. Her muscles may have atrophied somewhat. It's important that she use them, even ever so slightly, if deemed possible. Prayers sent.

Don't expect that she has regained all her energy after being in rehab. Sone long-haulers from COVID have weakness and other problems for months. Add the weakness from CHF and she can easily wear out - that can mean more falls. I would suggest helping her conserve her energy: fewer walks, combining tasks (toileting and wash-up while in the same room for example), and frequent rest breaks. Start "helping" a lot for a week so you can get an idea of her endurance. You can then try to get her to do a little more each week (walk a little further, do some lifting/resistance training, shorter rest breaks). Realize there will come a point where she has reached her max. At that point, you must decide if you can handle the extra work or need more help.

Can you get a physical therapist in to work with your Mom? They can also survey your home a give you suggestions on changes to the environment, medical appliances, etc. It's amazing how a few small adjustments can help them.

And I agree that you should give her a few days to recover from the move. Even simple changes can have a big impact on ill people. Maybe discourage visitors, or keep to one at a time.

Make sure she is at least getting up out of chair to stretch and use muscles for rising at least every 15 minutes to half an hour. These muscles are critical to get safely on and off toilets, beds and chairs. She does not have to walk from the chair, just rise up, take deep breath and sit down. Ensure she is using her muscles as much as possible and not being lifted by person assisting and don't allow drop into chair, encourage "slow" sitting into chair. If she needs major assistance, then just give assistance but continue to encourage she use her muscles or the situation will only get worse.

Try to walk at least every hour. When walking, make sure she is walking with a gait belt and pushing downward on walker (to regain arm muscles) with good form, it is not a shopping cart and she needs to be inside it walking (many elderly lean forward and push it like a grocery store cart which leads to falls and lack of muscle building). Try to walk her a few feet every hour and back to chair. If to the restroom, even better.

Feed a higher than normal protein diet temporarily to build back muscle loss (can be hard on kidneys but muscle loss from injury is severe, every one day of bed rest and little exercise equals a week of necessary rebuilding of muscles so you can imagine after an injury and hospitalization how many muscles are gone). What you saw was probably the only time she was able to walk.

Studies have been done and some patients (like my Aunt) never fully recover when they are in and out of hospital several times over a few months. I had no idea and would have brought her home instead of rehab because she can no longer walk safely from the hospitals refusing to walk her or do any therapy due to her dementia. Abuse. They don't even try.

I have to move into the hospitals and rehabs in order for her to get any help and actually participate during therapy with verbal cues in order for her to get the care she deserves. I would just show up and find her sleeping even though orders asked for her to be up and dressed and in activity room at all times to avoid sleeping all day. If you want your life to be easier and your Mom to be able to continue to do some self care, don't ever leave her at these places without family watching. It is horrific what I watched and I can only help my own family member. Other patients were ignored or neglected unless family showed up. That is when suddenly they are cared for and sadly, many are left there to die. Rehabs have some permanent residents on Medicaid.

With Medicare and her recent CHF and Rehab, she should be approved for PT and OT so take advantage of this. It may be a hassle to schedule and supervise but important right after discharge. I highly recommend that a family member be present and observe. Eventually you can use some of their techniques and exercises after she is no longer eligible for services.

She may need OT and PT to build up her strength because even the transition home has taken a toll.

If she is elderly these kinds of moves are exhausting especially with the health issues she has.

Make sure she eats well or has protein shakes and she needs extra rest for a few days. She needs to be hydrated and may actually be dehydrated causing more weakness.

I have work colleagues in their 20"s still suffering awful post Covid fatigue.

What makes you think the falls are on purpose? Did Mother have any attention seeking behaviours before Covid? Some people hate help & others seem to like it....

Well your mom has CHF and had Covid. Both things cause extreme fatigue. If she just came home today it probably really took a lot out of her. Try to get home health for her at home and pt to help her get stronger and to keep an eye on her vitals. It takes time to get over the Covid. Is she on diuretics for her CHF? She has been through a lot and may have lost her confidence. I hope she feels better soon

Is anything different happening with her vision? Facilities usually have hard floors that don't change color or texture. At present I'm very conscious of balance problems that are vision related.