How do you get your stomach to stop hurting when there's nothing in it?

Ok so I went to this Mongolian restaurant for dinner last night. But when I was trying to go to bed, I ran into the bathroom and threw up. I know it's gross but stay with me. I woke up about 5 more times that night to do the same thing. My stomach was hurting so bad and kept trying to throw up, but I had nothing left in me. How do I get my stomach to stop hurting when there is nothing left in it?