3 year old with dog

My 3 year old son took off his pants and underwear and was in a corner with his dog. As I peeked in to his room to my surprise I found the dog licking him! I walked in and asked him what he was doing and he stated nothing. I wet my pants so I am changing. I then asked him well why wouldn't you change and why would brownie be licking your private parts. He stated " you saw that." I asked him "was brownie the dog licking you" .... at first he denied it and then I told him he was lying and he shouldn't lie to mama. He told me the truth. I put him in the bath and explained to him that nobody touches is private parts. My husband and I had a long talk with him about his pennis. I asked him if anyone had done tis to him and he said no. I asked him who told him to do this nad he said his brain. I told him then he needed to tell his brain that penis' are for peeing and thats what it is for. I also informed him that dogs have germs and that he could get sick from the dog licking him. He seemed to understand but what else should I do? Should I be worried that something else is going on. I do not suspect anything at Pre-School ut should I be worried. HELP a frantic mother

[margypops]

I dont think there is any problem other than he had wet his pants and he let the dog sniff and lick,it he is   an innocent doing something he didnt realise was wrong, you did the correct thing and  told him it wasnt a good idea, now forget it, but be aware and keep an eye when he is playing sometimes at this young age children simply do whatever comes into their head,