Testing Woes....

Hi all. So here's my current situation. I was hired by Aramark about 3 weeks ago. So about 3 days in I was taken to get my ID to get in the building by the person who runs the payroll and money stuff. They asked her if I had been tested and she said no. They gave her a form saying that it had to be completed within 30 days or my ID would expire. Now I would consider myself a heavy smoker, averaging about 3 to 5 times a day for 4 years. I have never been tested in my life so I don't really know what to expect. That was 17 days ago. I stopped smoking as soon as I heard this news as I cannot lose this job. At this point I'm wondering a few things. Will they actually test me or did the girl just sign off on my forms? I don't want to ask her about it as to not arise suspicion as it's not supposed to be an issue. I've been around friends who are smoking still around me a fair amount. Should I get a detox kit? Or wait it out because I know pot clears out of your system in 28 days. I haven't been flushing my system with water that much but I do walk about 4 miles a day. I have a high metabolism rate and weigh 160 pounds. I was thinking about getting a home testing kit to see if I'm clear or not, but they're expensive and I would rather get the detox instead. The other thing is do they have to give me an advanced notice on this test? Like a day or so. Sorry for the rant it's been tough not smoking but I'm excited to get this over with because this the first actual tolerance break I've taking and so far succeeded in.