How do you know the difference between a heart attack and anxiety?

Sometimes you Don't: Sometimes a panic attack will look just like a heart attack. Sometimes chest pain will put you into a panic attack because it was an underlying heart attack. The best advice that i can give you is that if you are worried it is a heart attack then you should be seen by a physician. If it turns out to be a panic attack then this will relieve your mind and anxiety. If not, you did the right thing.

You don't : This is why a good medical workup is important.