I Have Mild To Moderate Pain In My Upper Abdomen,

I have mild to moderate pain in my upper abdomen, about an inch above my belly button. It feels like pressure or fullness with the occasional crampy feeling and it seems to come and go. It's onset was sudden while I was eating dinner tonight. Belching seems to relieve it temporarily. Is this most likely gas pain? If so, what medicine can I take to relieve it?