How common is it for a woman in her 20's to have gall bladder problems?

To start off with I will be 25 next month. For the past about 4 weeks I have been suffering from nausea and queasiness and I don't have to eat to feel this way. About 2 weeks after feeling like this I went to the doctor and she said she thought I was either pregnant or something was going on with my gall bladder which I thought was kinda weird. They gave me a pregnancy test and it came out neg. They took blood work, and I had an ultrasound done on my gall bladder and they said everything looked fine. The doctor put me on antibiotics and gave me some nausea medicine to help. If I don't feel better after I'm finished with the antibiotics I'm gonna go back and have a test done to make sure my gall bladder is functioning correctly. The symptoms I have now are nausea, fluttering sensation over right rib, constipation, gas, fatigue, get really hungry, occasional headache, and occasional heartburn. I am not having any pain anywhere though. I also wanted to add that my mom had her gall bladder removed a couple of years ago b/c it was only functioning 2%.