What am I experiencing right now??

On August 1st I lost my virginity to my virgin boyfriend. It was very magical consensual and all I would have ever hoped for. Romantic and comfortable (except for the normal pain ofc). We used protection, for sure. The next day I told my mom and she decided to take me to the doctor to have birth control prescribed. I’ve been taking birth control for 3 weeks and I took my first pill on the Sunday during my period. Okay now that I have all the back ground out of the way, let’s get to the point. A couple days ago, I think Tuesday?? I had unprotected sex with him (I’ve never missed a pill not even by a second) anyway flash forward to now I have INTENSE ITCHINESS in my vagina.. YES.. INSIDE.. and it hurts so bad too it also feels so sore but I don’t understand because the last time we had sex I was feeling okay down there the next day. All of the sudden yesterday I got out of the shower and immediately I felt so itchy like the walls inside of me where itchy af it’s so painful. I also looked in the mirror opened up myself and saw white discharge in the opening!! Please tell me what this is and tell me how I can make it go away without having to go to my mom and telling her