Spotting 35 yrs after hysterectomy at age 70. What does this mean?

This question comes up once in a while and the best advice is....
Contact your doctor.
If you have a Gyne contact them otherwise your PCP can do an exam and order any needed tests.

Is this for you? - go and get yourself examined. If it was a total hysterectomy I shouldn't have thought there was anything much up there that could turn sinister, so meanwhile try to breathe easy. More likely a touch of thrush or something like that causing irritation.

But ask somebody qualified to have a look and set your mind at rest.

Go to an OB/Gyn now. It could be serious or not, but that's who will make the determination.