Is it normal for my dog to lick my penis???

Hi I'm new here, I was in my Nan's and I was upstairs watching tv, the dog came upstairs and sat next to me so I stroked him but then he started to sniff my pants on my private parts. So I unzipped my pants and he started wagging his tail, I pulled them down a bit and he licked some of the hairs on my penis then he wanted more! I was a bit shocked so I just pushed him away. Then when I slept in my Nan's, he came in the bed with me and started sniffing again so I opened my shorts a bit and he licked my balls and then I took them off and lied there with my legs open and he sucked my dick I loved it and turned over and showed him my bum so he started licking it, I went asleep to him under the covers sucking my cock so I stroked him while he did this, is this normal??? Someone please help me! What should i do, he keeps trying to enter my pants???