If you’ve got a hangover stomach ache the best thing to do, even though you don’t want to, is to eat. Even a cookie, pretzel or cracker will help. The best thing you could’ve done is to eat a small amount of food before you went to sleep.
To prevent a hangover, stomach ache, headache or otherwise there are some simple precautions you can take.
Read the article, Prevent a Hangover to prevent this from happening to you the next time you drink too much.