I woke up with pain under my rib cage, could it be a gallbadder?

[Debbieorah1129]

I woke up this morning with a start pain under my right rib cage. I thought perhaps it was a gas bubble but despite taking GasX and tums the pain persists. It's now been a little over 7 hours and the pain is slowly getting worse. Though not crippling by any means it is definitely more than noticeable. I have not noticed it getting better or worse with a deep breath or pressing near the area. Could this be a gallbladder attack or gallstones? If so when should I get it looked at further? Should I wait to see if the pain continues to get worse? It feels like a sharp side stitch that someone would get from running, but I didn't do anything strenuous over the weekend or injure the area in any way. For more information I am a 31 year old woman, relatively healthy though a little overweight with a moderately sedentary lifestyle.