I feel like my life is going to end at this point..

Okay, so for the last month I saw posts on how its unhealthy for someone's heart rate to stay over 100 beats per minute while resting and I feared that my anxiety was going to make my heart rate go up and up and never go down til I get a heart attack.

I managed to deal with it until this week. Not only had I been drinking during the weekend which made my anxiety worse but I went for a long walk on Tuesday and when I came back I began to seriously worry how my heart was beating fast, to the point where my anxiety convinced me that it will never go back down to its healthy rate. I felt so weird and scared at the same time. My heart rate did go back to around 70-80 beats when I convinced myself it was all anxiety but this seriously left me hopeless, depressed and unable to do anything that raises my heart rate because of this. Can the mind really do this? Can it make my heart stay beating fast?

I'm super frightened! This mainly happens during the day and I do feel more relaxed at night but now I'm think my days are numbered because of this. :'( Any help? Thanks