It had been years since I fell off from not unclipping, but a couple of months ago, I just did it wrong - unclipped on my usual left side, while my center of gravity was to the right. In front of some very experienced riders, who probably thought that I'm in idiot. But there was no injury apart from pride.

As to feeling stupid, I think it's a normal part of life. There are people I know who never feel stupid, but that's not a complement.