Hi I am 18 and recently broke up with my ex every time we had sex it was unprotected and he did cum in me every time. the last time I had sex was about a week ago. Last weekend I was drinking and got drunk I didn't feel good before Friday night but i drank anyway. I ended up feeling really funny for about 3 to 4 days and now I am feeling sick all the time after I eat and have a slight pain in my lower stomach/lower back. What could this be???