I'm a 23 year old male medical student (2nd year), I have an excessively sedentary lifestyle, I have not regularly exercised for more than five years (and thus lack muscle tissue), and my BMI is around 25.1 (190 lbs, 6 feet).
For the past five months I have been experiencing increasingly discomforting chest pains. I am not sure whether they increase only in frequency and duration rather than intensity, due to the long period of time. In any case, these are long-lasting sensations, not very intense, but lasting for hours at a time. They take place most often while I'm sitting down over a book, when I'm slouching, and when I'm wearing overly-tight pants. I am reasonably sure I have no symptoms during exercise.
Sometimes, though rarely, the discomfort is accompanied by headaches. These headaches are at the back of the head, and are strange as they seem to affect only the left side and then spread to the right. Sometimes I will experience goose bumps (cutis anserina) only on the back left portion of my head. I am unsure, however, if the pain itself is lower down the back, but it seems to be related to the chest problem. Sometimes, I will also feel slight nausea, and I generally more off-balance. (I find that automobile rides are now a source of nausea whereas this was not the case earlier.)
Last summer I consulted my family doctor about the headaches only (not having experienced chest pains at the time), but after my EEG returned fine the doctor dismissed my concerns as "medical student hypochondria". The whole affair is extremely unsettling, and I find that constant uncertainty is starting to have psychological effects. Please help.