Hi newbie here...I am going thru the same w/my Shih Tzu baby..He's 7 weeks. Now when i brought him home he was completely trained on his paper. No accidents. But then i caught him eating his poo. Well i kept telling him No!! no!! and pulling him back by the scruff on his neck(not hard).Well he then went a couple of times after that ...buttt not on his paper...i screwed that up..as i now thinks the No!! was for not to go there..now i have him confused..my fault. So now i am keeping an eye on him..and will just keep piking it up..and disposing..hoping it will eventually stop.