Package Handling Questions

I applied for a package handling position at my local UPS Hub on 05/19/2010 (which is only two blocks away from my house), and for about 2 months I checked the UPS site daily to see if I had an appointment to tour the facility.

I finally got an appointment last Wednesday (7/28/2010 at 5:00PM) and ended up being the first one there. The HR lead us through the facility into a room, and there were about 8 or 9 other people there for the tour and the HR representative explained to us what our hours would be, the 3 shifts and how long they would last, etc.

Afterward we all went into the back of a truck to observe 2 package handlers unload a truck, and while everyone else was standing there watching I helped a little bit and threw a few of the packages onto the conveyor belt.

After that the HR rep lead us to the office where she asked each one of us to come in one at a time, in order of our arrival to the facility, and although I was the first one there a few people cut in front of me, which I let them do humbly.

Once inside the office she asked me a couple questions (Basic info), and I explained to her that I wanted to work the night shift. And overall she seemed to like me, and at the end of the session she told me she would run a background check on me and check my previous employment history and call me within a week and I shook her hand and left the facility.

I don't have anything on my criminal record, and I've had one job previously as a general employee at a movie theater which I quit last October (with 2 weeks notice)

My questions are:

1. Is this a good indication that I might have gotten/will get the job?
2. I'm 18 and still in High School, but I will graduate this December. Are they still allowed to hire people in High School as long as I'm 18? (Nothing in the qualifications about a diploma/equivalent.)
3. Should I call them to express more interest in the position? because I really do like and want this job.