Rash on help soon B day soon?

K this is long but please read all cause I need help now. K so i started swimming this year on F.day and have been swimming everyday for about 3 or 4 hours a day everyday and it is Sat. On about Mon. i got a rash in between my legs and down my legs where the white holed part of it that kept rubbing up against my leg and i wasn't shore if it was because i got a new bathing suite at Wall-Mart and it kept rubbing up against my legs or because it was chlorinated the day before. It hurt but by the time i went swimming the next day it felt better. Today when i got in it hurt like CRAP DX (the rash) but i had fun and about after 7 min of swimming later I felt better, swam for about 3 hours then got out. Ate dinner and when I went to my room my hurt. There's about 3-5 little red things that are at the top of the head where the bathing suite was rubbing a bit. My pool is mostly clean but just the tinniest bit dirty. I'm 13 and my B.day is in a few days so please tell me what to do to get rid of this. EX. how long it will take to just go away, should I put some cream on it, see a doctor, not swim for a bit, etc. I need everything that works cause I want to be fine for my B.day also does putting it is salt water work? Thanks ^__^