Rough one

Tuesday was back squats 5,5,5,5,5

When I did this workout I warmed up with part of the CF warm up and did a couple of lighter sets of 5 then jumped into the workout. I did 225, 245, 265, 285x2, 225. I've never failed at squats before this workout when I hit 285 I failed on my 3rd rep, didn't quite make it out of the hole. Maybe I'm being a little sissy but I hurt my back about a year and a half ago squatting 385 (was a bad technique issue), so when I think of going heavy on squats I get a bit gun shy. Since getting my level 1 cert. I've tried to be a form nazi on myself and make sure I do everything as properly as I possibly can, so I think I've been a huge squat cheater for the amount of time I've been squatting, mainly because I haven't really been getting down low enough, now I've got to really work at getting consistent with my depth and back position and get my numbers up.