Asking for a fren...

I am a single father with a 14-year-old son. I knew this time was coming but now I fear I am close to my wits’ end. I have seen evidence in his bedroom, the laundry room, and the kitchen. I know this is normal, but how much is too much? Things escalated last week when his hockey coach called me in for a conference. I have noticed my son has been taking a lot of penalties this season. It turns out he has been intentionally going to the penalty box to pleasure himself. I lashed out at him when about this and things have been awkward around the house this weekend. Am I overreacting? I know I have to talk about this with him in a calm setting, but I always find the thought of this type of discussion horrifying. I am losing sleep and I don’t want to succumb to letting his other father deal with this, but what should I do?