I'm a novice myself and have had a lot of trouble getting down the squat so take what I say with a grain of salt.
Your bar position looks a tad bit high to me to be a low bar squat. You'll also notice that your weight shifts onto your toes at the bottom (look at your heels come off of the floor). Your knees seem to be too far over your toes which is probably a consequence of the bar position and shifting your weight forward.
I think you could place the bar a little lower on your back, set your knees early, and sit back more.
I think the weight stall was a little mental too. Have you been doing a light squat day yet?