You could very well be going through either perimenopause or menopause, I would sure see a gyn about this and ask for some hormone tests as well. There are several that are very accurate, I like the saliva test, it tests for progesterone, estrogen, DHEA, testosterone and cortisol. You can also have blood drawn for the same, but, the blood is only a "snapshot" of what is going on at that moment.
Postmenopausal bleeding always needs to be checked out.
are you pregnant its a funny ?
Are you going through menopause? I would suggest you see a gynocologist.