How do you feel after lifting?

But I was feeling tired when I was lifting 4 times a week. 3 days works better for me.

Ya it's possible to overtrain. OP how often are you lifting?

Just three days a week. I do about 15 min of HITT sprinting afterward and take the rest of the days off. I don't think my deficit is too large, I'm at about 1700 calories, -20% TDEE, but I do kind of struggle with eating enough protein. I'm about 150lbs and 5'6" and am averaging about 80g a day. I know that's probably not good, but I concentrate on the protein portion of each meal/snack more than anything else. Do you think that's what's causing the fatigue? I also have a 3 yo and 4 month old that still wakes at night.

After squatting I feel like putting an icepack on my lower back.

Actually, now that I think about it, on days that I deadlift, my lower back really aches the next day! But that's the only soreness I feel.