Every HR is different. I've had some call me the next day, one I had to wait 4 weeks for. I recently accepted a job as a Unit Tech, and when I went for my initial interview, I overheard the HR interviewer telling the receptionist not to put in calls from students wanting to know about summer jobs, that it was a waste of time
. Then she looked out and saw me, and said "Can I help you?" and I replied "I'm just a student here to waste your time." She was quite flustered
Anyway, I guess my point is, give 'em a call, it is their JOB to talk to potential employees. Don't get too worried about the delayed response time, HR sometimes has different priorities than the unit you applied to. The manager in the CCU I'll be working in was quite eager to hire me, even though the HR woman thought I was a waste of time.
Good luck, hope you get the job