My friend works in admissions at a nursing school and she advised me to not be afraid to follow up, even relentlessly. As long as you are friendly, nice and understanding in demeanor, she says they will help you. She said that the people she responds to are the ones she knows are just going to call back if she doesn't! So don't be afraid to call and follow up, it shows you care. Just be nice and realize they may have thosands of files to check and hundreds of phone calls.