Had oral sex. white,sore spots came up and went away after few days. but came back, and now i have sore red throat with yellow-ish spots? oral thrush?

Get checked: It could be thrush, which is a fungal infection, but you can get other infections, such as chlamydia and gonorrhea, in the throat. You need to get checked.

Exudates? : Exudates can be common to a sore throat either be infectious or not. Oral thrush while not as common are white and have a plaque like appearance usually found in either immuno compromised states or usage of steroids.