Quote Originally Posted by Python View Post
As I made to come back on the path, it was as if someone kicked the bike out from underneath me. Down I went whacking my head really hard on the path.
Sounds to me like your tire/wheel was knocked out from under you by the pavement edge. Sure, the grass may have been the same height as the pavement, but the weight of the bike on the grass and soil would cause you to be lower than the pavement, and you probably hit that pavement edge at a shallow angle, knocking your bike out from under you.