Karma pays me a visit

I have been a soccer referee for my daughter's league since last fall. I received three hours of basic training and worked six games in the fall in the 7 and 8 year old division. In the spring, I got an additional three hours of training so that I would be qualified to work in all divisions. I worked four more games. So, with training and experience, I have been at this for about about 12 hours.
I signed up because they begged me to. Because no one else would do it. Because I can't say "no."
I did not sign up because I love rules. I did not sign up because I know how the game is played. I did not sign up so I could wear these terrific thick polyester shorts. And I sure as hell did not sign up because I enjoy sucking.
Today was Soccerfest. Soccerfest is a tournament with special rules. Teams of 4 players each play two seven minute halves. No keepers. If the ball is played in the goal area, it's a point for the other team.
My daughter did not play in Soccerfest, but I volunteered to ref, because they had a hard time finding volunteers. Perhaps this is because they schedule it for Memorial Day weekend. I digress.
My first four games were in the U8 division, and I did okay. I blew one corner kick call. Since there are no keepers, I had a hard time keeping track of which team was attacking and which was defending. It sounds easy, but those girls get all mixed up, too.
My second four games were in the 10-14 division. For the most part, things went well... until the last game. The last game was the black team versus the green team. The green coach, let's call him, oh, I don't know....Mr. Small-Johnson... was loud and obnoxious from the get-go. It is my philosophy (and the philosophy of the league) to let the kids play- not call ticky- tack fouls or incidental handballs. One of his kids flopped down, and I didn't call a foul- because there was no foul. He called the kid over, and in his "loud secret" voice, told the kid to get more aggressive, because obviously the refs have been told not to call anything. He said it had been happening all day.
His team was awarded a goal after the black team played the ball in the goal area.
At the second kick, the teams switched sides. He yelled "Why are we switching sides? We have been playing the same side all day?!?" and the other coach replied that they had been switching. Small-Johnson mentioned that "It says in the RULES that we aren't supposed to switch"
I turned around and said, "It also says in the RULES that coaching is discouraged, and that players are to wearing the same color jersey. (One of his kids was wearing blue)"
He said "Well it's hard not to coach when the reffing is so bad"
Now I know he wasn't just bitching about me. He was bitching about all the refs, all day. And he was probably pissed because his team sucks.
Then, I missed a call. I did not see whether or not a green player played the ball in the goal area. Both coaches agreed that the kid had, but the kid didn't say he had, and I didn't see it... so I couldn't call it. I blew a call, and it went Small-Johnson's way. And it knocked the black team out of third place for the tournament.
I told the tournament director what happened, that I hadn't seen it. He said if I didn't see it, I couldn't call it. So technically, I was in the right, but really, truly, I was wrong. I was terrible. I should have seen it. Everyone else saw it.
All the referees I have yelled at in my life are smiling, I think. I feel awful.