Why is my home test still coming back negative??

Hey all,
I've been clean for about a month and a week now, still pissing dirty. I am about 210 lbs and very active (workout everyday) and have been taking B2 to help speed up my metabolism, so I was just wondering if anyone has any ideas why I am still coming back dirty? Any other ways to help speed up the process? Possible test in 2 weeks so I'm getting kinda worried...
Thanks in advance!

What was your smoking history prior to stopping a month ago?

Pretty hefty, multiple times a day. I expected it to take a bit longer than a month but am hoping so see some clean pee sometime soon...