If i smoked a blut 3 weeks ago will i be go for a drug test?

okay so i weigh 170 pounds bench press 220 and im about 5"9 i have to get a drug test today for pre employment. about 3 weeks ago i smoked 1 blunt. yesturday i drank 7 bottles of water plus a detoxifacation drink. today i drank 3 bottls of water before the test. plus more duing the past week because i was sick with the flu. should i be good ? please re-asure me lol