Test Coming Up- Any Help would be appreciated

Background- 27 y.o., male, daily smoker for 8 years (only 2-3 hits a day), 5'11, 160

Just wondering if any experts can answer a few questions for me. I recently was offered a job on 9-17 that I accepted pending a drug screen. Boss went on vacation next week. Thought I was going to be able to take the test this week(9-27 through 10-1). Still haven't heard anything about it and it is Tuesday, so i assume I will have to take it Monday at lunch.
I took one Illadelph hit on Friday and have been abstaining since. I took a home test (dipstick) on Sunday 9-27 and passed with a very very very faint line, so faint that I took 2 more the same day and still got a faint line but a little darker. I took another one with first piss of day, midstream, on 9-28 and got a little darker line, and took another first piss of day on 9-29 and it was definitley darker. I decided to buy a CVS FC test that same afternoon and passed with a line that was pretty dark at each end but faint in the middle. I am pretty sure that I will pass on Monday 10-4 but I was wondering if this low time frame seems unusual, it has only been 12 days since I quit, and was wondering if any of the experts think that I should still try to SUB.
I also think that this low time frame might be due to my metabolism. I used to weigh about 235 lbs 1 year ago. I joined the gym and started going 4-6 times a week and now I have lost about 75-80 lbs since then. i also quit smoking for a job for about 2 weeks starting early June of this year, and about 2 years ago I quit before I lost all my weight and it took between 25-30 days for me to pass a home test.

So what happens if I still decide to sub and get caught or the temp isn't right? Would i be better off just using my own piss and try to dilute, or am i just being paranoid and should I be ok just taking the damn thing straight up?

Sorry for the long post, any advice would be greatly appreciated.