Visit the dysautonomia or autonomic dysfunction forum and see if you can find a doctor in your area - vertigo, racing heart, trouble sleeping etc may all be related to the ANS and may take a visit to a dr who has knowledge about ANS issues - you can google autonomic dysfunction, dysautonomia or autonomic nervous system and see if anything sounds familiar
sometimes it takes many years to get a proper diagnosis, but a cardiologist who has ANS knowledge is a rare and great thing =)
i agree see a cardiologist,are you sure he dosent take any types of drugs..i had serious palpitations started about 4 months ago,every time i had a ciggerrette it started, so i stopped smoking (after 25 years) and hey presto they completly stopped.lucky me.i had to give up caffein aswell.good luck.
Given the symptoms you note, a Cardiologist would be my recommendation for a doctor to discuss.
Going back to before the heart pounding started I ask if he was very tired from working and going to school. I did the same myself during a couple of years in my undergraduate years and I know I had worked myself down to a sorry state, but I didn't notice any heart problems in my case. My point, if the heart symptoms started after the heavy work schedule started the cause may be exhaustion. What about coffee/coke (caffeine)? That may "pick one up" but it can cause heart symptoms, as can anxiety. Be sure you have the timing figured out before taking further with a doctor.