i have had a pain in my chest now for 5 weeks on and off.it is a stabbing pain and lasts for minutes and sometime a small pain which lasts for hours the pain is somtimes near my armpit,middle of chest and near nipple.i can breath normal when it comes on.but i panic and stress alot and when i comes on i sweat alot and panic thinking i am having a heart attack.i had a ecg at the doctors and it was normal.is this all in my head