My guitar's broken... please help?

I have had my black squier strat that was a store model for a little under 8 months and was part of the standard strat pack. It was awesome in the beginning, but last month it fell off the stand and part of the neck hit the the edge of a wall. There was a little dent on the flat part of the neck right by part of the 3rd metal fret. It's right by the highest pitched string. The fret (still the metal part) now has a slight curve above the neck starting at the 2nd lowest string. Now there is a problem on the 1st 3 strings of the high E string (the highest one) where all 3 frets sound the same when played. The only way to stop it is to physically take the string out of the notch on the nut and slide it off so it's pressed against the side of the nut. And that's only temporary because the tension eventually snaps the string back into its notch and the problem happens again. on the 2nd highest string's 1st fret and the 3rd highest one's 2nd, there is a buzzing when played. I've adjusted almo