Head Vs. Bed

Ouch! I jus hit my head on my bed (which is of the top bunk only sort), but the story doesnt end there, oh no, to reap my vengeance upon my bed i attempted to demolish it using my head.
yeah i did jus hit my head again. That's twice in one morning, i've had this bed for years and it hasnt moved, i know exactly where it is. After a few bumpy months at the start i grew aware that i have to duck to get underneath it, but woefully as of today my head forgot this simple but o so important piece of information.
Thus leading my double cranial infractions upon the suprisingly sturdy metallic bedframe.