Did I have a heart attack or am I loosing my mind? Need help calming my nerves

Hi, I suffer from a lot of anxiety and I am starting my third year of uni this week, so yesterday I smoked some weed to chill out and watch a movie. I sat for a while but began feeling unwell and it got progressively worse. I measured my heart rate and it was normal and so was my body temp, but I felt horrible.

I felt pressure in my chest, I began shivering, my left hand cramped up and hurt a bit, and I felt weak and began panicking. I thought able it calling someone for help but figured I was overreacting as usual. I fell asleep after a while and woke up feeling okay, apart from some pain in my chest. I still feel the pain in my chest, so I figured something had to have happened.

A lot of the symptoms of heart attacks and anxiety attacks are similar, so I wanted to ask you how likely is it that I had a heart attack? I am 21 years old, I sit in front of my computer a lot but I excercise daily and I eat okay, I am not a diet freak but I also don't eat only junk food. I will probably set up an appointment with my doctor for Friday this week, but I cannot fall asleep due to feeling like I could die anytime. Please let me know what you think about what happened to me.