Hi and thanks for the query.
Spotting in a menopausal woman(10years) is always considered abnormal until proven not to be so. Also, having lower abdominal pains that go towards your back, I will ask you to take this serious.
There are many causes of spotting in postmenopausal women from non dangerous ones like infections of the
cervix, vaginal to potentially dangerous ones like cancer of the cervix,
uterus etc.
The only way to know what the cause is, it to meet and discuss with you
OBGYN doctor. She/He will be able to ask more questions, examine you and may be ask for tests if needed. I suggest you follow through and get the definite answer that having a list of possibilities.
Hope this helps and at least provides guidance. If you need more information, please come back to us.
Hope you get the answer to your worries soon.