Should i Substitute or not?

Well heres the story...i smoked for 4 months straight and then quit for about 22-23 days...then smoked the last 3 days straight....if i stopped today...and my test would be at the earliest next monday (may,31) what route should i go in...i can get clean urine the day of the test no problem for substitution...so which would be better? and also, i have a few freinds that are willing to give me clean urine, but my gf would be the easiest to get it off of....shes on a high dosage of birth control...would that show up on the test? thanks for all the help.