I have white covering on tongue it goes away a little during day then comes back. and a soar throat lasting 3 weeks is it hiv?

Probably not: See whether you can remove the white on your tongue by running dental floss across it. If not, see your physcian and find out whether it's candida. Have your throat checked -- this could be anything from a bacterial or viral infection to a vasculitis to simply breathing through your mouth while you sleep. And since you need to ask, get a HIV check since you've been at some risk.