Hello and welcome to HCM.
Thank you for your query.
As you are post-menopausal, a light bleed which usually does not recur, should not be a cause for concern. But the presence of lower
abdominal pain along with this, does indicate the possibility of some underlying condition, which will either have to be diagnosed or ruled out.
I would advise a physical examination, speculum examination and an
ultrasound. Which can all be conducted by your doctor on the same day, within an hour. We can find the cause for the same, and if required initiate treatment at the earliest. Do not worry, post-menopausal women do experience these issues, but they are not serious and can easily be treated. All forms of cancer, will be considered only after ruling out other causes.
I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications at: http://doctor.healthcaremagic.com/doctors/dr-shoaib-khan/64581 . I would gladly help you.
Best wishes.