Can anyone help

[Tate1981]

So my last workout on thursday evening i hit 110kg 3x5 on squat and they felt good. This morning i went to hit 112.5kg and had to stay at 100kg as my form had gone to shit and it felt extremely heavy. I just couldnt get bent over today as my back was killing me. Anyone critique these as to why the pain and why it felt so heavy albeit 10kg lighter??? Help! Very frustrated.
YouTube

[Satch12879]

What did you do away from the gym between Thursday and this morning?

Also, what weight is this set you posted the video for? 110kg, 112.5kg, or 100kg?

Did you complete 112.5kg or did you not even try?

Why did you drop down 22 pounds?

Can you back up the video so we can see all of your stance? The knee caving is something.

[Tate1981]

I pretty much havent done a great deal outside of the gym since Thursday and today. Had a few beers and chilled out basically.
This is 100kg. I didnt try 112.5kg as when i was warming up, i got up to 100kg and it felt very heavy and was causing pain in my low back.i stayed here and done 3x5.
I'm not sure i can back up the video. My recording wasnt very good, citting off my left foot.
Looking back at it, my stance maybe too wide. I seem to be dropping hips down, not back.

[Tate1981]

Another thing i find is my first rep of the set always seems to be forward on my toes and takes me another rep or 2 to really get my hips back.

[Mark Rippetoe]

Aside from the first rep, they look pretty good. Stance is a bit wide. So I guess you felt bad today and gave yourself permission to deload down to 100. Congratulations. You have stopped training, and started doing RPE.

[Tate1981]

Thanks for the reply Rip. Does it make much difference what time you actually train? Reason i ask, last week i was training later on a night after work and a full days eating. And things fekt good. Today was first thing on a morning shortly after some breakfast. Anyway, i'll hoy some food down, refuel until Tuesdays workout and get that 112.5kg. 3x5. Thanks.