Will I be able to pass my drug test?

I use to be a daily marijuana smoker until I went to jail for 45 days. I smoked one bowl when I got home on june 19th, and then made the stupid mistake of taking a few hits off of a joint on june 24th. I'm 5'0 in height, and usually weigh about 110, but I gained 8-10 lb over the 45 days that I plan on losing soon. My first probation meeting is july 12th, will I be able to pass the drug test if I drink water and exercise? I want honest opinions and answers, but nothing rude please. I'm scared but I plan to stay 100% clean after this. If anyone knows of anything that might help, besides detox drinks, it would be much appreciated. Thanks!!