Please help really bad crotch itch!?

Ok i have had this for probably over a month now! im a girl 15 years old and i have really bad itches on my crotch its like around my bikine line but also like right in the middle on the surface (not inside) i don't shave down there i have never had sex so don'tt say crap that involves that and this has been going on for so long! i dont no what to do all my underwear is 100% cotton i wear loose basketball shorts as much as i can although the itching is worse when i wear jean shorts or tighter shorts also iver stopped using my normal soap and body spray ive done everything everyone has said! and plus it is kinda red to like patches of red someone said takeing a oatmeal bath would help could i just use regular oatmeal? and someone said vinager would help but i would be afraid to try that .....just regular cooking vinager? well please help me! and i have tried lotion to