Last night I saw my orange guy using the litter box. He was in the middle of it squatting and peeing but his tail was quivering. When he was done he covered it and got out. I had seen him do this before ( with tail quivering) but this time I noticed there was some urine on the rug and wall. I was not happy. I cleaned it up and have been worried that he may have a spraying issue. Our home does not have any odor problems ( visitors cant believe we have 4 cats because they don't smell anything) so could this just be a case of him missing the box? Maybe I need to get those tall backed litter boxes. He is about 3 years old and is neutered.