Gall Bladder Cholic possibly ,does it radiate up and in your back high up as well, is the pain severe, have you had a fall or run into anything as a broken Rib really hurts especially whyen you breathe.Get it checked out if it contiues, if you think its Gall Bladder, low fat diet helps there are certain foods can trigger it put it into the sreach Engine.
Why keep waiting? It's on your right side below your rib cage. Chances are it's your appendix. If so, the longer you wait, the greater the chance is that it might ruptue. If that happens, you're in greater danger. They can do a blood test to see if the problem is coming from your appendix. I'd get myself to an ER now if I were you. I'll say a prayer for you.