ATTACK: double wrist grab from behind

ATTACK: double wrist grab from behind
1. double wrist grab from behind in hamni. uke grabs both wrists. step back as you curl wrists up to the sides of hips, then point wrist down as you step back under one armpit of uke. your shoulder in uke arm pit and hands in front of you, you lead uke into a roll.
see video1
see video2
see video3

I'm kinda confused as to why I keep landing on my head on my right sided break fall. Tuck chin, bounce more off tippy toe, swing leg back more?
Taisabaki kata notes
9,10 don't bring feet so close together
1,2 keep elbow in and bent, forearm not parallel to ground otherwise can't block roundhouse as well. watch feet being wider
kiai with the punch and heel strike as if to direct the spirit to that foot or fist.
lean more weight forward than back
don't punch with shoulder forward
3,4 bring knee up higher, block and kick and rechamber
7,8 bring feet further apart