I would definately buy some home test kits. 35 days might not be enough time for you to be clean. There are some on this forum that have taken over 60 days to get clean. If you use the dilution method the day of the test you should be fine but drink gatorade instead of water and don't exceed 40 ounces. Make sure you piss midstream and I would presume you would be fine. I was a daily smoker for 15+ years 2-5 times daily and it took me 35 days for the home kits to come back negative. I'm 6'1'' 230 pounds though. I passed my test after 49 days with flying colors and now it has been 66 days and I'm keeping it that way. The stress was just so unbearable to me and I'm not going through that kind of stress again. It is just not worth it.