I've had my 3 year old dog since a pup and he was really well house-trained but for the past few months he's started peeing in the house I really don't know what to do, he's quite a nervous dog but he also doesn't like going outside in the rain its really hard to keep an eye on him all the time because he always finds a way to make a mess in the house, he just pees in his normal places but if we block him of he would start weeing in a new place.please help! Oh by the way he is a 3 year old cavalier king charles spainiel if that could be any help.