Can gas cause pain in chest and pain when pressing down on pelvis?

Yes: gas is a creative ailment -- it can cause pain in the chest, stomach, pelvis. if passing gas alleviates symptoms, then that is a good guide. however, it is a good idea to have a physician examine you. there are labs and tests and physical evaluation that can be done to help narrow down the cause of the problem. you wouldn't want to ignore a serious problem.