I'm so sorry to hear you crashed --I was hit by a truck a month ago and can relate. For the first few days, I got tired pretty quickly, too. It does get better, though.

My bike shop wouldn't throw my helmet away until it had been completely destroyed, so I got to take a sledge hammer to it out back. They are surpisingly sturdy. It took me 4 wacks before I broke the plastic. To have split yours in half had to have been quite a nasty crash.

Take care of yourself and get a lot of sleep. From my experience, the aches and pains do start going away after about a week.

Susie