Just stay out of school until you're feeling better. The 5th sounds reasonable to return. Ideally people would not be in school when they're sick, but the reality is if you're in school you're going to get sick in the winter. Lots of babies have RSV, I don't know that it predisposes you to having it more as a teenager.
Ok. Thank you for answering! I do have a question though. How long should I stay out of school? I was planning to not go tomorrow, and have a doctors excuse to go back on the 5th. Is that good or should I stay out longer. A lot of kids have influenza but go anyway and the school won't shut down to prevent infections. On a sort of related note, I had RSV as a baby and have had bad lung function ever since I can remember.