Can too much drinking in a short period of time cause a rapid heart beat?

here's the deal i haven't been the same since my father died on january 12, 2011. Since then (and it's june 29th 2011 now) i haven't been able to stay sober for longer than 10 days at a time. I drank a lot in the span of 5 months. I also have a caffeine allergy so i don't know whether it's the drinking that's causing this or my caffeine consumption. I had this symptom for the last 2 weeks or so on and off with some minor chest pain. The last time i got palpatations it was the caffeine but i still get them on days when i don't have any caffeine. It's not like i can run to my doctor and say "hey i drink too much" i'd look stupid. I just hope i didn't really **** up my heart and it's not too late i'm only 18. I never did any drugs or smoked cigarettes and i don't have panic attacks or ainxiety. I did try 4 lokos a few times but i stopped drinking them since february and will never have them again TOO DANGEROUS. Any advice would be appreciated thanks