What do white spots in your throat mean that disappear?

I know that white spots usually mean strep throat, I've had it a number of times, but they seem to have reduced since last night. I don't feel like I usually do when I have strep. I just have a sore throat and I'm congested. I first spotted the spots around noon yesterday, towards the night, they multiplied and got bigger. This morning I woke up and they got smaller.