[keefer]

Nasty business
I would be surprised if it snapped due to something seizing but either way the head will have to come off to inspect how bad the damage is. If the valves are intact they may well be bent.
Keep your eyes pealed on flea bay for some second hand heads. But as you say first step is to whip her out and have a look.
Hope it gets better from hear on in Mate
someone with moor knowledge than me will be along shortly