Gallbladder?

I have had pain under my lower right ribcage for some time. It sometimes radiates directly around to my back. On and off I feel 'full' or 'bloated' with frequent gas and burps. I sometimes have heartburn or my whole stomach feels upset. Lately whenever I have physical activity, like going to dance I have severe sharp pain under my right ribs and feel sick. Caffeine or rich foods seem to make it worse, I once thougt I had a lactose problem, but am wondering more and more if my problem may be more ociated with my gallbladder? my big question is does your gallbladder have to hurt all the time? I get sick after eating greasy stuff...but not all the time is it accompanied with sharp pain...only sometimes. I saw the Dr. monday...they are running bloodwork now, and i have an ultrasound in the morning.