I can't believe how weak I am, /fit/.

I have been training for a year and a half. The best I can manage on squats is 135lbs for 3x5. Actually scratch that... I failed my last rep on my last set today. Deadlifts also trouble me quite a bit. I can't figure out the form. I either bend too much at the back or I stiff leg them. The best pull I worked up to was 300lbs but after reviewing form I realized it was all back and barley any kegs involved. My knees were locking out way before my hips. Now I deloaded back to 190 and trying to figure it out.

I don't really care about bench but that is only at 120lbs for 3x5. My press is at 80lbs for 3x5.

Pic related. Kid squatting as much as I do.