Topamax and flank pain

I have been on topamax for migraine prevention for a couple of years now, (50mg a day) and just recently have started to have moderate to severe flank pain. (right side) This pain sometimes radiates to my upper back...I was wondering if anyone else has had this kind of side effect when taking topmax? Last year around Feb. I had the same problem- ended up in the hospital- they thought it was my gallbladder. They were going to remove it but none of the tests they did could confirm that was the problem. It never was figured out but eventually went away. Now its back, and I'm trying to get some feedback before I go back to the doctor and spend a fortune on more tests that result in nothing! Any feedback would be GREATLY appreciated. Thank you!

Eeeek! I started 50mg topomax in Aug for migraine prevention. I have two questions...I forgot to take it one night and ended up with a week long migraine but it was also during a nasty rain storm and huge weather changes...so could it have been from missing just one dose or is it more likely I got a migraine from the weather changes (weather caused my migraines before medication).

Secondly...what are the first signs of kidney stones? My family doesn't have a history of them so should I be less concerned about getting them??