Could Frequent Urination, Burining Around Vagina After Having Sex Be Yeast Infection?

I am a 16 year old girl who had sex the day before i got my period and 2 days later i have been feeling the need to urinate frequently and have a pain in my lower back and my butt bone area. Also an irritation almost like a burning sensation around my vaginal opening. And don't know whats wrong i also just got rid of a yeast infection about a week ago.