What should I do about my sore throat?

I think I'm getting a sore throat. It's not exactly painful to swallow yet. But when I do swallow I can feel all phlegm in my throat and it is kind of hard to swallow and it hurts just a little bit to swallow. I constantly need to swallow every 5 minutes since I feel a lot of phlegm in my throat. I took a throat lozenger today, but it didn't seem to work. I also feel runned down, very tired and running a slight fever. What should I do to make me at least feel a little better?