Navy Loan Repayment? Also, Officer questions?

So i have recently decided that I want to become an officer in the Navy. Right now i'm a college sopre and am going to a community college and will soon be transferring to a University. I've looked into the NROTC program but i'm pretty sure you must be a senior in high school to do that. Also i have heard about BDCP, but not only am i going to a community college right now (it makes you less competitive) but i have a low gpa right now. So my thinking is, is that i continue with school myself and once i've completed my BA i'll apply to become an officer. But my question is, can i get a sign on bonus, or is there some kind of student loan repayment option that i can use to pay off my school? And i've heard about an official "Loan repayment" program that the Navy has installed, but from what i've read, it appears that it is only available to those who are enlisting, not to future officers.. Can some one help me PLEASE!!! THANK YOU SOOO MUCH!