Oh, Annelise, that was a bad fall, and a frightening fall.
When I fall, my brain loses all power over my limbs. I go down like a tree cut down - crash. My husband says I look like a shot deer when I lose my balance, I just crumble without resisting. And yes, that is something that happens to us when we have PD.
The only way of preventing falls (most of them) is to pay close attention to every step, every wrinkle in the rugs, every little bump on the ground.
And even more important, concentrating on what your legs are doing. If you stop thinking of what your legs are doing, your legs forget what to do. We must constantly tell our limbs what to do. We can not take movement for granted like we did once.
Going up or down stairs carrying something requires extra attention. If you get distracted, your bum leg (the one that is affected most by PD) will simply stop walking and trip you up. You must concentrate on every step, or that leg will not work. Going up stairs it will drag so you stumble, going down it will collapse and make you fall.
Your fall was worse than most. I often have one or two blue and bruised or bloodied knees, but falling on your head is dangerous. You might ask your Dr.. for Amantadine - without it my legs hardly work at all.
I hope you never fall like that again, no wonder it has frightened you. Please be very careful.
God bedring,**

birte

*Oh, that hurts.
**good mending.