WELL 13 days clean when you only smoke a bowl every other day is not good. But if you workout regularly and have low bodyfat and drink lots of water you would be good. I think what EVERYONE should do is take home urine test. The cut off levels for Home test are the same as LAB TEST. Some will say different but remember no matter if it is a dipstick or a machine 50/15 is 50/15 that is one thing that cannot be disputed. The only thing i have heard about lab test is ONE if you tested positive for opt then they could say exactly what made you test positive. Second in rare cases home test will not give positive or negative result. In that case the lab would be able to go further and give you a PASS OR FAIL determination. Remember the bottles that come in the home kits are the same and ship to the same type of lab as doc offices do. ALSO if you read the home test say IF TEST IS NEGATIVE there is no reason to ship to lab, mainly because results will be the same.

Hope this helps