Not sure what to diagnose my self with for the symptoms I have with my vagina

I'm 13 and I'm afraid to tell my mother about my symptoms I've been having with my vagina, because I've had sex and I'm afraid I may have an std.. But I've only had sex once so I dont even know if that's possible. 

My symptoms include; 

itching , discharge (normal), burning, and cut like feelings. 

Can someone help me ASAP. 

Thanks soo much :)