Thanks so much for all your advice!

When my coach saw my banged up knee yesterday, he only said "welcome to the club" and grinned.

I had my front tire fixed and tried again. This time all went well! I find it works when I unclipp the foot I stop on and leave the other one clipped in. The only thing is to get used to not put the unclipped foot back on the pedal.

Well, Thursday afternoon I'll go with our club to sunny Florida for a one-week training camp with a whole bunch of coaches. So I hope that by the time I get back, I know how to bike with clip shoes...