I'm freaking out

Help! I'm really freaked out. A little earlier I was hugging my dog and I felt that my left nipple hurt and it felt a bit wet, so I went and checked (i wasn't wearing a bra, idk if that's important) and something that looks like breast milk was coming out of my it. The thing is that I'm 16, I'm a virgin and my period ends today. I'm not taking any weird medication and I usually don't have this kind of problems. I don't want to see a doctor unless I really have to because of some personal really bad experiences. Help!!