i took a drug test on the 5 panel drug test and it came up clean i think. i smoked weed once about 3 weeks ago and havnt smoked for a year before that. i took the test and it came up fine, all panels had 2 bars, but the thc bar looked just a tad bit fainter then the others, is this ok or am i just paranoid, do they use the same kit at drug testing clinics? thanks