Hello, Im a 16 year old female. Ive been having a sharp pain in my lower left abdomen for the past two days. Its worst when i Walk and while i sit it just burns a bit. Also my neck and shoulders have been huting more then usual. I have been sexually active, however I did not miss my period, and my pregnancy came back negative, but at first it look positive then the one line seemed to disapear. I have researched online and many women who say they have had an ectopic pregancy have stated that they also missed their period. Im not sure wether I have an ectopic pregancy, a cist or possible a kidney problem. Should i go to my family doctor or gynecologist. Please help me out If you may know anything. Thanks