Kidney disease at 20?

[MC95]

I am a bit concerned for my health. For the past 2 days I have been having abdominal pain that has been mainly in my lower right side, but as the days have progressed it has spread through both sides of my abdomen and into my back. I have gone to the doctor and they have ordered an ultrasound to check for anything wrong with my gallbladder. However, based on research I have done I am honestly more worried about kidney disease. Should this be something to even be concerned about?

A bit of background history. I have had similar problems in the past. There would be times when I get random nausea and heartburn for no reason, then it would go away after a week or so. I have also had problems recently (within the last 5 months or so) with nose bleeds. Nothing like pouring blood or anything, but just when I blow my nose there would be blood. This is something I have heard is associated with kidney disease.

My diet for quite awhile now I am ashamed to say has consisted of a lot of fast food (burgers, fries, shakes, soda etc). Usually on a daily basis...

I have leg pain and itching all the time. Mainly in my calves. This isn't a recent symptom for me. I have random bouts of difficulty breathing, I feel tired most of the time, I have off and on changes in urination (increased/decreased), and I get a lot of chest pain and shortness of breath.

I am concerned at this point that maybe my doctors are looking into the wrong areas, but at the same time I don't question it because I didn't go to medical school. But it is something that concerns me, and I am wondering if this even sounds like It could be the issue.

I have described my symptoms to 2 doctors, and both said gallbladder may be the culprit. Is this right?