Helllo Im Male 18 Years Old Iwas Feeling Pain In

Helllo im male 18 years old iwas feeling pain in the chest a month ago and went to the doctor,i did ultrasound and also the thing he puts these stickers on the chest he said everyhting was fine with my heart and the pains actually more or less went away after that(probably it was in my head placebo has an effect on me a lot),so what happened is i was with some friends and snorted some (0.2 g)cocaine first time in my life and didnt like it,the thing is since then it was 3 days ago i notice my heart beating a little faster at night and whn lying down left side i can actually hear and feel my heart like its beating stronger..im not sure should i go to the doctor again or is it anxiety?