No, no reason to fear. Even if you don't come unclipped, which is highly unlikely, the worst that would be liable to happen is that a big piece of your shoe sole will be torn out. That's what happened to me the one and only time I didn't get unclipped. If you didn't unclip and your feet stayed on the pedals and you landed on the right side, instead of the left, you might get gouged by the chain ring (like in that pretty photo that Rich posted a while back). But that could happen with clips and straps, too.
P. S. I hadn't read Spic-Mick's post yet when I wrote that. Obviously there are exceptions!
But that, too, could happen with clips and straps.