The first real tourney I was asked to do, I went through the same thing. I did two games the first day (a Saturday), but then we got rained out the rest of the day. We made everything up on Sunday, which meant I had to do 9 games that day. Fortunately, I was 18 or 19 back then, so I had a little better chance of keeping the energy up.
Unfortunately, I was in such a rush that morning that I forgot to put on sunblock. My face was so burned that it began to blister and peel that night. I'm probably going to pay for that later in life. Maybe that's why I've had such negative feelings towards tourneys, because that was one of the last ones I ever did until a couple years ago.
As for the sore muscles, check out
this thread, my man. Send your wife or daughter out to Target to pick one up, and pronto. You'll feel much better.