Set 1: The first rep is perfect. But when you lower the bar, your first movement should be pushing the hips back, not bending at the knees. It should be an exact reversal of the concentric portion of the lift. Since you lowered the bar without pushing your hips back, you were in a poor position to begin rep 2.
Set 2: Your setup was poor. The hips aren't pushed back enough and your torso is too vertical. This results in you trying to squat the weight up.
Set 3: Same as set 2. Your hips aren't back far enough.
Try to duplicate the form for set 1, rep 1 on every rep of every set. I also think it would be a good idea to work up to your working sets a little more slowly. 135, 185, 225, 275, 315, 365. Treat the lighter weights like they're heavy. Set up and pull every set like it's a 1RM no matter what's on the bar. You can only perfect your technique if you practice perfect technique.