I Was Bitten By Some Type Of Bug Or Spider

I was bitten by some type of bug or spider about 2 weeks ago on my jump seat at work. I am a flight attendant. I have been putting a topical on top to prevent itching. I have a bite mark still that is the size of an almond and a ring about 2" in width. The color has lightened quite a bit, and the swelling has gone down, but it's still noticible.

Any ideas what I may need to do?