I had a full hysterectomy 20 years ago. Today at 61-years-old, I'm bleeding. What could cause this?

This is a question for your doctor.
You will find a wealth of possibilities on line if you type this in, and if you wish to be scared to death for likely little reason.
See your doctor.
Best of luck to you. We have had this question many many times over the years if that's any comfort at all. You can look up the answers top of the timeline in the little magnifying glass search section.

This is a frequent question. I have attached a link from here on aging care so you can see a wide range of replies.

Please see your doctor to take appropriate action.

https://www.agingcare.com/search?term=Vaginal+bleeding

Laurarob, best to see a doctor as this could any anything. Hopefully it is as simple as a popped hemorrhoid.