Hello, I have a 2 year old male rottweiler, he is very calm, and neutral towards strangers (neither friendly nor aggressive). He is very well trained and walks off-leach perfectly, even in crowded areas. I often take him to dog events and let him loose between other dogs and people. Three weeks ago, he mated for the first time. I took him yesterday to a dog event and he was a totally different dog. He was trying to hump every dog regardless of breed, size, or gender. He attacked every person trying to greet him. He also was very stubborn in commands; I had to pull him hard for him to focus. I asked few people around my area who knows about dogs; most said that its a result of sexual disturbance and will go soon, and he is bullying after mating. A trainer at the event recommended that I get him a muzzle for a short term period, and socialize him with people till his issue has ended. What do you recommend me to do??