i am level 6 now and i just killed some skeletons when all of the sudden i cant swing my sword any more. it just hangs there in my hand, unusable. what can i do i know its equipped?

Unequip or equip a different weapon and re-quip it. Happened to me alot too later on in the game, I would see my weapons only to go into my inventory and see dragon form claw armor (sorry if that spoils anything.) where my human form weapons should be.