pregnancy and pains

I'm 17 and almost 6 months pregnant i don't smoke, i used to do crystal meth but i quit about 1 month before i got pregnant but i have been pretty healthy ever since. I have been having palpations some chest pains that are really sharp and then headaches that are really sharp, i'm pregnant so i have obviously had alot of tests done and nothing is wrong, i am concerned aboout my drug use in the past and how it could be effecting me now with my pregnancy, i can never relax in my mind and i think that might be the main cause i dont know can someone help me??