E-Screen VS. At home test.

Hello everyone!

I am new hear and I have a question.

I just got offered a new job and they wanted me to take a drug test. When I first started looking for a job about 4 months ago I quit smoking. After 2 months of non-smoking I got pissed off that I had no call backs for job interviews so I smoked. About a week later I got the call I had been waiting for, a job offer. I went in for the interview, nailed it and got the job. I told them I needed to give 3 weeks notice to my old job and they said ok. That was 22 days ago. Yesterday I went to the local drug store to get an at home test for weed. The test said I was clean(neg. for pot). Then today I had to drop for my job. They told me to go to the rehab area of my local hospital because that is where the drug test are done. They use an E-Screen machine to test the urine sample. Basically my question is what are the chances I failed the e-screen after 2 months off then one week on then 22 days off(weed)? I have not heard back from anyone to tell me I failed but I am still worried. Also are the at home test good? Thanks.