Sore Glutes?

[Tate1981]

I've hitting a wall on Squats and getting some pretty bad low back pain. I've been trying to bend over way to much i think, dropping my chest. Anyway, i restarted from assuming the squat position, actively keeping chest up then moved onto some light tempo squats keeping tight, chest up and driving hips up out of the hole and my glutes the day after are very sore. Is this normal due to me not using them properly prior??,

[Stefan Theimer]

Yes.

Conventional wisdom around here is that the eccentric portion of movements (down on the squat) will make you sore.

You've essentially tripled the amount of time you spend on the eccentric by doing a tempo squat. Even at light weights that will likely make you sore.