Hi, I'm 15 and a reasonably new referee (I qualified in December) I had an U13s game today which wasn't particularly eventful apart from a corner situation. The ball was out of play and a corner was about to be taken when a player, in his own box, elbowed another player in the back of the head. I immediately signalled for a penalty until I realised I couldn't give it because the ball was out of play so I reverted my decision. I had a word with the player but I wasn't sure if I should give a red or yellow for violent conduct or unsporting behaviour as I couldn't tell if the elbow was accidental. I had a mentor at the match and he said that a red would've been harsh especially as it's a kids match and no one wants to see red cards however he did say I could've cautioned the player. Despite this, I'm still unsure what the best course of action could've been.