Could I be pregnant??

About last week I had unprotected sex three times with withdrawal. Today I woke up at 12:00am with SEVERE stomache pains. I was about to throw up about 3 times and my diarrhea was like water coming out in spurts. It was awful! (But note that I also have acid reflux disease and I'm lactose intolerant and ive been eating pizza for the past three days, and I have been eating w.e I want) so I'm not sure if it's my stomach problems acting up or if I'm pregnant; morning sickness