Most people have a 0 mph fall or two when learning clipless. Assume you will.
Very true. It happened to me a couple of times. Both in the presence of a young woman, which seems to be a prerequisite for joining what, in this forum, is called joining Club Tombay. But more to the point, both times I landed harmlessly on my shoulder, with nothing wounded but my pride. I was very surprised at how little it hurt, and this is probably part of getting over ones' fears.