Update. I took my first at home drug test just now. It has been approx 3 full days since my last hit. There is a control and test part...and the instructions say that a line on the 'test' part would mean negative, and no line is positive. After doing my test, there was a very faint line next to 'test' so I am assuming it's negative! The line is very very faint though, but you can definatly tell it's there, it's just extremely faint. I will take another test in a day or 2.