HX fall off bed

This morning HE wake up early this morning and quickly she wants to lie beside HX. As usual, hubby and I will get out of bed to prepare ourselves for work, leaving them on the bed. Most of the time HE is still asleep while HX has already wake up but playing in the cot.
However as I am washing my face, I notice that HX is gone to another side of main bed while HE is beside her in the middle of the bed. I am not alert enough to relocate HX, instead I proceed rinsing my face. Just in a second, HE :"wou..." I notice something wrong, and found HX has gone off the bed and ended on the floor. I am shocked! Quickly I picked up HX and angrily accusing HE for pulling HX to the open end of the bed and I also slap her at the arm. The next scene is both HE and HX are crying.
After a while HX has stopped crying, but there is red bump on the right side of her head. Then I console back HE. She still deny that she has pulled HX. She claimed that HX has gone there herself.
Now thinking back, it is not impossible that HX rolls herself there. I shouldn't blame HE rightaway, making her a blacksheep. Nowadays I scold HE a lot, I am afraid it will become the pattern of communicating which is unhealthy. I should be careful and control myself. My temper has gone out recently which I donno why. Because I am too tired of juggling 2 kids, work and renovation thingy? Tonight I got to adore HE more to compensate.
Hope that HX do not have any problem due to the fall.