I have to take a drug test/screen (I'm not sure what it is) to get a job. My friend is the manager andhe gave me the low-down on the process. You go to a doctors office, they take your sample and put it into a machine that spins it like a centerfuge and then analyzes it. The whole thing takes about 20-25 minutes. What are they doing?
Sounds like theyre trying to scare you - and it seems to be working, as evidenced by your statement...
I'm a bit scared since I dont know what they're doing.
All urine samples undergo an initial instant-type assay screen as it is most cost-effective to both the labs and the client paying for the test. There are many different types of instant assays used by the labs, from your typical strip/cassette kits, to the EZCup, and to the EScreen. Ive never heard of any urine sample being placed in a machine and spun like a blender. Exactly how any analysis can be performed while the sample is (hopefully) capped and spinning?

Sounds like a bunch of BS scare tactics, if you ask me.

I'm 5" 7' - 150lb, I'm an everyday toker, fairly high metabolism. By the time I go into to take this thing, it will be about 3 weeks since the last time I smoked. I plan on going through doing the steps from the dilution guide. How do my pass chances look?
Only periodic home testing will realistically tell you your chances of passing. Anything else is all guesswork. If passing the U/A is really important, would you want to rely on guesswork?