Wow... Kellis... if i was in your situation... and this probably isn't the best of all ideas... I would probably see the note with my pipe and weed, look around (i'm guessing it was late at night and they were upstairs), take your pipe and weed and get it to a safe place (Presumably NOT in the house or your car) and call your friends asap to let them know to be on the lookout for your rents calling theirs. When you get back home after hiding them, if they heard you they probably got up and are waiting up for you.... so explain your reasonings for smoking pot and if they don't accept it. A. They don't have your pot... so your weed and pipe is at least safe and B. This is the time you bitch them out.... hardcore...

Personally... if my parents made such a big deal about it (and they would if they ever found me... and i've had my fair share of close calls) then I would wage war and don't back down against them... I've gotten my parents to ease up by continuing to rebel against them (in the areas i disagree with them on, mind you) but that's just my two cents... and i'm high...