I think I just had an allergic reaction to cheddar?

I (F, 28 years old,, 169cm, 77kg) just ate a piece of newly bought red Cheddar. Cut a piece off and ate it and went into a videochat. During the videochat I noticed my upper lip had like an itchy bump. I tried to scratch it away (like an uneven part of your skin) but it didn't work. I looked in the mirror and there is a white spot and red around it and my lips feel swollen. Even the lower lip looks slightly swollen to me. When I laugh, it looks like there is fatty tissue underneath it.

I have no food allergies. Apparently I am allergic to one tree but I don't notice it. Is this something I can test by putting Cheddar on my arm? Should I mention it to a doctor? Can this be a one time thing or should I know avoid Cheddar? I have always suspected to be "allergic" to some kind of cheeses because my mouth used to itch when I eat like Swiss cheese. But nothing was ever swollen. Idk not sure how to handle this new information?