make a mistake or just overthinking it?

I recently got an interview for a job in which they had my original resume. I had updated in the mean time applying and getting the interview. I took the newer one to the interview. The newer one doesn't contain the job I had as a teenager(I'm only 20 so it was recent) and I added a job that is very PRN and isn't an RN position. It's health screening. I had a job during college that is still on there.

So my question is, did I hurt anything by adding that job to the new resume? I never thought of putting it on because it's so PRN but the manager told me he would allow me to use him as a reference because I am on very good terms with them. Or am I just really over thinking it?

I really want this job and it was my first interview as an RN so I can't help but to think of all the things I may have done wrong =( They are doing background checks so I won't hear anything by sometime next week and it's killing me!