What can be done for swollen labia with pain?

Hello doctor,

I am a 25-year-old female with no children. My husband and I have been together for six years. We have no extra-marital affairs and I am 100 % sure of that. My right labia is swollen and is very painful to touch, even a slight breeze of air causes extreme pain. The pain is similar to a sunburn. It is painful enough to make me cry. The swelling starts from my right vulva next to my vaginal canal and goes all the way to my anus. The area with the worst pain is next to my perineum. This started as a painless lump in the size of a peanut that could be palpated from within my vagina with a finger but not visible externally. This was about a week ago. Now, it is huge and painful.

My labia is three times larger than its normal size and very red. There are no discharges, no foul smells, and it is not itchy. I am managing the pain with Clobetasol topical cream and Mefenamic Acid orally. The pain disappears instantly with the cream but I think it is also making the swelling bigger (steroid?). I am on my third day of Co-Amoxiclav 625 mg (twice a day every 12 hours) but I think this is what caused the swelling in the first place. Also, I tried to do a sitz bath and it only made the condition worse. Just a few hours ago, I had trouble breathing (allergy?). I have never been allergic to any medication before. Any impression or advice would be appreciated.