Freaked out!!

Omg I am so scared!! I was laying down on my back in bed and suddenly I saw... A bump? I am 15 weeks pregnant and I don't really have a bump, more like a little fat belly BUT the bump was not where it was supposed to be, it was really down there, it included some of my pubic area and a bit above and it was not even centered!! As I said I am 15 weeks now and definetly that's not where the baby should be right now!! Is it something wrong with me? Few days ago I had an appointment and everything was fine. Should I worry? I'm home alone and I'm freaking out!! I took a few steps around the house and the bump was gone when laying down again... I wasn't painful or anything...