vaginal swelling, birth control side effect or infection?

Ok, so my obgyn but me on seasonique birth control. it was a bit too expensive so i asked him to switch me. now im on Apri. I have never heard of it, but i started about 5-6 months ago. for about a month now i have had a hard time being sexually active due to what i think is swelling inside of my vagina. it hurts when i try to have sex and feels like i am too tight to let anything in. also, the next day after having intercourse is very painful. i wake up to being swollen a lot more on the outside and being very sore and sensitive. i dont know what this could be caused from right off hand but i think it could be my birth control causing it. please help