If you do NOT have crushing chest pain--and I mean like a ton or two of elephants sitting right in the middle of your chest--if you can walk around your house, or even go up and down stairs without barfing, and if you are NOT drenched in a whole-body, ice-cold sweat--then you probably are NOT having a heart attack.
As a victim of panic attack myself, I would suggest you read, read, read about panic disorder and join the anxiety community here:
http://www.medhelp.org/forums/Anxiety/show/71
And then, make an appointment with a mental health counselor or psychiatrist who specializes in panic. You will feel a lot better once you put yourself in the hands of the right specialist.
By the way, your cholesterol and cholesterol medications should have no effect whatsoever on your panic.
Take those anti anxiety medications!