I have the same problems as many here...if i smoke weed i get anxious...I was really thinking about quitting....but getting high is such a great thing, it helps me to deal whit many things, i NEED it, so i couldn't just stop smoking weed....

What helped me was, i realized this is only psychological, and now i enjoy smoking again...i only take 1-2 hits at one time....wait a few minutes, and if i feel the anxiety coming, i go for a walk, take a ride whit a bicycle, drink water, i keep myself busy whit something so i don't pay attention to the faster heart rate, and i KNOW this is only in my head, i will not get a heart attack, i just simply calm myself...I don't smoke that much now, so i get really baked...and i try to smoke my own grown weed, because that causes far less times anxiety, and also eating weed is good for me, or green dragon...