Buring sensation while peeing

So im 16 and me & my boyfriend have sex alot.  Only a few times has this happend and this is the longest its ever been, im not itchy or anything but everytime i pee it burns really bad ! Ive had this for a little over 2 weeks and i tried using the uti medicine but i stopped because i noticed one time it came out & it had a bloody color to it & it burned really bad ! PLEASE HELP  
Ps | i thing it might be bacterial vaginosis but im not sure ! 😭