It was okay. I think I would have enjoyed it more if your author's comments weren't so loaded with self-pity. You kind of put me in an "expect it to suck" mood so everything seemed... Y'know... Sucky. The tweening of him backflipping across the ground, the lines, definitely the voices, there were several things you could have improved upon. My biggest advice would be to try to enjoy what you do more. You don't have to brag about it if you don't want to (though honestly, from a psychological/marketing standpoint that would be best), but don't tell people to hate it in advance. If you honestly believe it sucks then one is forced to wonder why you'd show it off. Either you think the rest of us love sucky things or you just want people to tell you you're wrong and that you're actually wonderful (which, let's face it, is pathetic whether it's a flash, a dress, your weight, or anything, if you think it's bad don't expect others to disagree :P ).
All things considered, it's not a bad flash. Keep it up. You'll get better. Before you know it you'll have flashes that YOU don't think are bad.