Why do i get pain upper right stomach almost every night?

past month or 2 almost every night (not exactly every night but usually only at night) i get this pain in the upper right side of my stomach (gallbladder runs in my family so i thought it was that) but now im leaning towards appendix..if its any of those. sometimes the pain isnt that bad so i figure its just my stomach acting up. and it goes away within a half hour hour the most. only two or 3 times it has been a sharp pain but only lasted a minute or two if that. sometimes when i press (right below rib cage on the right side) it does hurt. so i was leaning towards appendix. i am in the middle of switching doctors and never made an appointment yet, has anyone experienced this problem or ideas on what it could be? thank you.