How long will marijuana be detectable in my urine after a single use?

So i had to stop smoking because of drug tests. I smoked everyday up until Saturday, February 20th. I then stopped for a week while drinking a lot of cranberry juice, green tea, and water. On Friday, February 26th i smoked a blunt of exotics laced with kief between 2 people. The next day i then smoked a blunt of reggie and a blunt of exotics between 4-5 people. Since then i have not smoked at all and i have been drinking a lot of cranberry juice, green tea, and water also. I can now pass a drug test because i took one of those at home drug tests and passed. Anyway my birthday is coming up and i am having a party where there will be drinking and smoking. If i face a blunt or smoke a blunt between 2 people, how long will the marijuana be detectable in my urine for? Also, I weight about 120 pounds and am like 5'6. I believe I have a pretty fast metabolism too.

Edit: I have niacin pills and vitamin b super complex pills which I can take. From what I here, these help clean my system? Please correct me if I'm wrong, but how much of these should I take and how often if these will help clean my system?

Edited by o iToke o, 14 March 2010 - 01:57 AM.

niacin, b complex, dandelian root (look for a detox/herbal supplement)

If it's only one time and you've been clean it'll probably take 2-3 days maybe a week at the most.

niacin, b complex, dandelian root (look for a detox/herbal supplement)

How much and how often should i take the niacin and b complex?

If it's only one time and you've been clean it'll probably take 2-3 days maybe a week at the most.

Okay thanks. Thats what i was thinking but i just wanted to be sure.

running, sweating, steamrooms, etc. help circulate and remove stuff

i dunno about exact dosages but lookup how much the stuff is suggested for athletes