Please call your gynecologists' office in the morning and make an appointment to be seen ASAP, as 99% of us on this forum are not qualified to even make a guess. Your health is too important to leave it up to total strangers to try and guess what's going on. I wish you the very best.
What kind of spotting? If you have had your uterus, cervix, ovaries and tubes removed any discharge is very likely vaginal atrophy, especially if you have been feeling very dry. I agree that you should call your doctor but not panic.
I wish you the very best.
Call your doc first thing Monday AM.