Well from what i have heard, smoking once a month will be out of your system in about 3-5 days (depending on different factors). Well this was 2 weeks ago and you smoked very little. Also you haven't smoked 4 months prior. My guess is without diluting or anything, you will be fine by next time you take a piss test whether it be at home test or at LabCorp. But to be sure do another at home test to know where you're at. Hope that helped. Good luck.