peace of mind

I had a Medtox drug test Friday for my job, I believe it was the kind where they do pre-testing and send it off later.

I hadn't smoked for 40 days previous to the test, but smoked 4 days in a row previous to that 40 days, and intermittently so, about 2-5 times a week depending on the week the previous 9 months.

I am a bigger guy (5'10 230) but I ran and worked out 4-5 times a week during that 40 day period. After taking the test I took a home strip and found the slightest pink line I had ever seen, I spent most of the night frettering over whether it was even a line or not. My friends acknowledged that there was a line, but also acknowledged its profound faintness (talking maybe off-white here).

It's now Monday and I haven't heard anything yet, do you think I have anything to worry about? Or am I just being overly paranoid?