Why does my vaginal opening feel lumpy and a bit swollen?

Hi,

Welcome to icliniq.com.

At this young age of 18 years, I do not see any reason for you to get tensed. The vaginal wall is full of folds called vaginal rugosity, so this may be felt as lumps, which need no treatment. As you do not have any itching or soreness, infection is ruled out. The other possibilities are as follows.

1. If you are sexually active, then it could be any infection. This needs a course of antibiotic and antifungal for both of you, and abstinence till the swelling is fully gone.
2. If you have been roughly masturbating or using any sex toys, then it can cause swelling, which will subside on its own.
3. If you have been using a tampon, it can injure the wall of the vagina. Just stop using it till better.
4. Recent respiratory infection, which got transmitted to the vagina. It will also resolve on its own.

These are just possibilities, and I am sure you are absolutely fine. Just wait for few days, and it will be gone. Hope I have clarified your query, do write back. All the best.