Swollen Vagina

Okay so My boyfriend and I were having sex the other day, and afterwards I felt down there and it felt like something was there that wasn’t supposed to be. I looked with a mirror and it’s like something has swelled up and is blocking the opening of my vagina. The swelled part hurts if I touch it, try to have sex, etc. I’ve had a cyst once so I know it’s not a cyst. I thought maybe a yeast infection but it doesn’t itch, there’s no discharge, and it only hurts if it’s touched. I want to give it some time to fix itself, but in a week if it isn’t better I’ll make an appointment. Have any of you had what this is or know what it could be?