My squat is so bad compared to hip thrust . Also coccyx pain ?

Any tips for evening this out ? I've always struggled with squats . My joints hyper extend so I wonder if that takes part in it . Even body weight squats kill my quads.

I'm at 135lb for hip thrusts and I die doing 35lb barbell squats . Goblet is easier for me and I could go up to 45-50

Also I noticed my coccyx starting to hurt two months ago . No idea what caused it . I did have abdominoplasty with muscle repair ( post 155 lb weight loss )in September so i wonder if it takes part in that for some reason. I stopped lifting for two weeks to see if it would help and it didn't. I feel it hip thrusting alot I guess because I sit on it in position for the movement. It hurts when I sit anywhere . I started using a pillow under my butt and may even use a thick pad too next time . I had an x-ray done and it was okay . Has this happened to anyone else ?Thanks for any insight