symptom help please

Ok so I am starting to Greek out and am really worried earlier today I started feeling pain in my left under arm and now i can't even touch it without wanting to cry also had heartburn for past few days but with tablets it settles but today I can't seem to shift it I took a preg test and its negative I haven't had a period in over 3 months as mine are really irregular anyway so it's not a big deal has anyone else had this and before finding out they was pregnant or should I seek medical advice it's keeping me up worrying and also the pain in both my arm and my heartburn please comment am getting worried