dude i am going through the same thing. i took on hit i will be testing on 21 day of being sober. Most research one hit is upto 7 days so theoretically you should be fine. But if u find urself being easily paranoid dont do it? because they anxiety wont probably be worth the one hit....30 days is the min amount of time for most chronic user....7 days one hit is all u need to be clean according to research (but than there are other variable such body fat)....but yeah in personnel case i have been stressed out about this for almost 2 week now. If u trust science with all your heart, then all means take that puff:rasta: