Penalties of Failing Test?

Just curious, what sort of penalties are their if I'd fail a piss test? I'm applying for a job, and I'm almost positive I'm going to have to give a piss test. And I'm 18.

Also, I smoked about everyday all April. Before then, I was sober for about 6 months. I weigh about 130-ish. I smoked my last bowl last Saturday night. Will being sober for those 6 months help to get it out of my system faster, or is smoking everyday like that going to make it harder to get out? I might be going for a piss test in probably 3 - 14 days, hopefully longer if I can push it back more.