What Causes Nausea, Abdominal Pain, No Periods, Vertigo And Fatigue?

I'm very confused. For probably a little over a month I've been expiriencing weird symptoms. I have been getting randomly nauseous for no reason at all at all times of the day but mostly at night. It will actually wake me up. (normally even when I am sick I don't throw up but with this I have been) I have had an occasional stabbing type pain in my abdomin (but not very frequently) I have not had my period from 60 days. I have been getting vertigo (the other night it happened while driving, it was so bad I felt as if I wasn't even on the ground and everything was contorted) I also have been fatigued (but that's not uncommon for me at all so I don't know if that is related). What's going on with me?