A couple months ago I performed unprotected oral sex on male. It happened around 11 at night. The next morning, roughly 12 hours later I had a sore throat and a cough. It lasted two weeks with swollen and white tonsils. But later that day I had a small bump on the roof of my mouth that I popped and didn't worry about because I do have bumps that pop from time to time after eating certain foods.

Three weeks after my throat felt better I began to feel a sore throat again. I usually have post nasal drip so I'm assuming it's that but after eating a lot of sugar and salt and vinegar I also noticed a lager bump than last time on a different area of the roof of my mouth. After almost two days it's pretty much completely gone, but my throat still hurts a bit with a cough once and a while.

My questions are: would an std show up after about 12 hours? Is this purely coincidence that I had another bump, is it probably from the food again? Or is it likely an std?