Hey I'm fifteen and I just had a scan the other day. Depending on what you have your gonna feel different things. The scan starts with you laying on a table and a machine over your abdominen. Then your gonna get injected with this stuff to have your gallbladder fill. That won't hurt. After laying on the table for fourty minutes and can't move. If your gallbladder dosent appear the test is over and its already ruled abdormal. If it does fill then they put yoyn back on the table and inject you with another thing this time to see functioning of the gallbladder. If its not functioning properly you'll feel it. Goodluck and.I hope this helped.
Sorry you're going through that nastiness.
The scan itself is no big deal. It's boring. Really really boring. The shot they give you is no biggie either. That won't make you sick.
The only thing is that they feed you some seriously nasty high-fat stuff and that might or might not make you ill. It depends on your system.
Personally, I think if your doc says get the scan, then get the scan. You'll have an answer on whether your gallbladder is causing your symptoms or not.
Good luck and be well. :)