Certainly a pain in your abdomen that is relieved with urination can be a problem with the bladder. The most common bladder problem is a urinary tract infection. However, this usually causes pain during urination (which you have not mentioned) and the pain in the abdomen would not necessarily go away after you urinate. A simple urinalysis done by your doctor
in his or her office would be able to rule this out quickly which may be your best first step. Pain when you bladder is distended suggests that the bladder may be pushing on another structure in the area which is relieved when the bladder is empty. The bladder sits on top of the uterus and could be the source of the pain. Your ovaries and fallopian tubes are in the area as well. This could be a large ovarian cyst, but this would be an unusual presentation of one of those.
I suggest that you bring this matter up with your primary care physician
. He or she will want to examine your abdomen very carefully to rule out any obvious abnormalities. Be prepared to produce a urine sample as a part of your workup. If a bladder problem is suspected, but no diagnosis is made, then you may need a referral to a urologist