If i smoked three puffs of marijuana approx. 27 days ago.i'm 62yrs old 192 lbs, i exercise on the treadmill 3 times a week could it be negative res

Likely out of system: Cannabis has a 1/2 life in humans of 67 days , meaning 1/2 of the compound is out of the body in that time Urine is tested because it is detectable longest in urine .https://www.ncbi.nlm.nih.gov/pmc/journals/1832/. Detectability has to do with body fat, amount smoked , and sensitivity of test. One cigarette detection is about 3d, smoker of a few a week more like 7d, regular smoker 30d or more