Question about drug testing for THC?

I use to be a chronic marijuana smoker, as in three to four blunts a day. I quit about 4 weeks ago. Well exactly one week ago a friend of mine owed me some money and offered to give me some weed instead of the money and i took him up on his offer. Well instead of selling it to get my money back as i intended, i smoked it. It was some low to mid grade weed, nothing killer. I smoked about 3 grams of it over two days and finished it off about a a week ago. I go to take a drug test tomorrow and am a little worried about what the results would be. I know very seldom users can get the THC out of their system within about 5-7 days, and im a very small build, 5'11, 130 lbs. And i work out alot and do alot of running. Should i be worried about the test results, i have no time to get an additive or masking agent, but will my past chronic use ( that quit about 4 weeks ago) affect how quickly it leaves my body? Anything will help.Thanks in advance.