I think we've all done it.

My first time out with both feet clipped in, I fell twice on the same knee. (I did the old "clip one foot out, lean the bike the other way" thing the first time; the second time was me being stupid.) And again later, when I ended up sitting on the rear triangle of my bike. I've had a few near misses since--I can't talk and unclip at the same time, apparently.

It'll probably become second nature soon enough. Make sure the tension on your pedals is set low enough so that it doesn't take a whole lot of effort to get out. You might want to look into the multi-release (gold) SPD cleats if getting out of the pedals is a problem.

Hopefully your neck feels better soon!