it's not a panic attack...It's called "the fear". It can sneek up on experienced pot smokers. The fear lasts for about 10 minutes. The first 10 minutes is a roller coaster ride into the depths of death and the abyss of the unknon. After 10 minutes you come down and mellow out. It's ok we all get it sometimes.

The fear makes its introduction after about a year of smoking grass.