OK, here's the deal. About a month ago (give or take a few days) I got really drunk, and smoked a joint or 3. I haven't been smoking since I started my new job, because they do random piss tests. However, I'm getting hired on full time (off of my 3 month temp period), and found out that they require a hair test. So, how long does THC stay in your hair? Will it show up since I only smoked once about a month ago? And does that shampoo stuff really work?