I think that referee needs to have a think about why he actually referees. Talk about looking for problems ....
Actually takes me back to a game I played in many years ago. A team mate was complaining of bad guts way before kick off and had spent much of the hour before the game in the toilet, but as we only had the bare 11 he was persuaded to give it a go. Half way through the first half he sprinted off the pitch towards the toilet (at Regent's Park so a far old distance), unfortunately when he came back and asked to come on the referee told him to wait and then when play was stopped he cautioned him for leaving the pitch without permission. Then when he calmly explained that he was about to sh!t himself and therefore had to run off quickly the referee sent him off for swearing, and I got a yellow card for trying to defend my team mate (I was the captain).
It was actually this incident that made me take up refereeing ...!! Not entirely surprisingly his straight red card was overturned on appeal.