Ct scan was done and a trace amount of free fluid, which may be pelvic, was found..is this a serious condition? symptoms include swollen stomach and sharp pain..prior hysterectomy done in 2000?

This is common and considered normal in most cases. How it applies in an individual case must be decided by the doc who knows why the test was ordered and all other facts of the case.

All imaging results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Talk to the doctor who ordered the tests. Having said that, what you described is within normal limits. Wish you good health!