Re: My cat in 1 day has completly changed pls help
JusJim brought up something I was thinking of, too...that of an odor trigger for his aggressive displays. It almost seems like he is happy to see you and when he gets close enough to smell you, his attitude changes 180.
I read a book about a horse who did this. Every time the woman came outside and spoke to the horses, one horse would go nutso-bonzo, rearing, bucking, striking and squealing while rampaging around his stall or paddock. The owners were very sad, especially the woman who thought the horse *hated* her voice and couldn't come down to the barn and enjoy their horses.
The Trainer (a behavioral expert) came to view the problem and met the gentleman who took him to see the barns/horses while his wife finished getting ready and would meet them at the barn. The Trainer thought the horses looked wonderful, very nicely kept and happy and relaxed. Then, the woman came out the back door and trilled a happy little "Yoohoo, I'm on my way!" ...and one horse pinned his ears, lowered his head, swished his tail and shuffled his feet. As the woman got closer and closer, the horse escalated his behavior until he was once again, rampaging around the paddock.
The woman was almost in tears, so certain her horse hated the sight of her.
Well...it turns out that when she got close enough to her husband and the Trainer, the Trainer was just about knocked over with her perfume. He found a tactful way to tell them it wasn't *her* the horse objected to, it was her perfume. There was something in the perfume that set off a trigger in her horse and because a horse's sense of smell is so strong, it was probably so annoying it was painful for him. She stopped wearing fragrances at the barn and her problem was solved.
Lets hope you and your kitty have as easy a fix...