What could cause someone uncomfortable gas if it's not food or drink?

Lately I’ve been noticing that I feel gassy, but not the kind you can force out. I try to sort of wait it out, but I can’t ahem expel it, lol. The curiosity is that 9 times out of 10, I haven’t had anything to eat or drink in a few hours, and even when I did, it wasn’t what you would normally consider a gaseous food. No carbonated beverages or anything.. and today my last food was a small piece of cake around 3pm. Yet here it is 10:24, and I’m rather uncomfortable. The only way I’ve been able to get rid of it is by taking something.

I’m calling my doc tomorrow because this is getting annoying, but in the meantime, I’m interested to see what ideas you might have as to what the cause could be.

In other words, I’m not surrounded in any clouds of disgusting noxious fumes or anything. Hell, if I was, maybe I wouldn’t be so darned uncomfortable LOL