Possible heart problem? really scared?

hi, im a 17 year old male, an lately i dont know, seems like some tightness in chest a back pain or sometimes a pain in my left side, an sometimes a pain in my left arm, anyways i read stuff like this like a possible heart attack or cardiac arrest i think its called, but i dont know tho im just really scared an im a pretty paranoid actually EXTREMELY paranoid person about everything, i dont know if this is actually real or if its me just thinking about it too much an being panicking about it, i got a doc's appointment at the end of the month like the 30th i believe but idk im just really scared an paranoid an idk wat it is, about me im 17 eh 6'2 around that idk how much i weigh im not really fat or skinny either, i dont get much exercise im a inside type person, love gaming addicted to world of warcraft pretty much, an yea ill get bashed about being a "nerd" or being addicted to wow an etc its normal, but please ignore that an reply to me if u may have some sort of answer, idk just scared