Unsolicited advice:
1. Invest in a "gooseneck" phone holder if you're going to keep videoing your squats, etc. Rip should sell a line of these for $100 a piece, but he has too much decency, I think.
2. The bar is too high. That's why it rolls forward every rep. Read the book mentioned above.
3.
Get Some Shoes | Mark Rippetoe
4. Your head is coming up because you're looking at yourself in the mirror on the way up. Either find another gym or figure out how to avoid looking at the mirror.
Good luck!