Slight swelling in left collarbone, chest tightness sometimes, swelling tummy which is not soft...anyone knows why?

See a doctor: While maybe one of my colleagues can attach a diagnosis to this triad of symptoms, its a little confusing. First off it is difficult to know what you mean by a swelling collar bone but in a 29 year old female with chest tightness and abdominal distension I'd certainly want to know if she was pregnant, does she smoke, is she on birth control, time frame of symptoms, I think you should see a doctor.