Hi, So I'm not entirely sure how to put this.. but I'll try so if you can stick with it, much appreciated First up, my cat is eating and drinking and using the litterbox fine (although there is a little less poop than usual but she's eating less than before since I changed her diet to higher meat content, so she needs less of the good meaty foods than the Whiskas she used to have - she's not hungry). She has, however, started to become a lot more temperamental.. bipolar even.. She'll be perfectly happy one minute then the next be growling and hissing (she has never hissed before) at random, inanimate objects - the front door is the most common. There's no bugs inside, nothing new in the house, she's got plenty of toyys etc so not bored. She gets especially growly/hissy if you try to lift her which she always was a bit unhappy about, but never aggressive. Now she'll bite and bite hard at certain people. For example, she was laid on my dad being pet, purring away then bites his arm and doesn't let go WHILE PURRING!!! and when we prize her off him, she looks confused and licks the area she's bitten. She's done this a good few times, unaggravated and not always being pet (as i know that can get to them), literally just as people walk by sometimes - she's gone for ankles/arms/foreheads/noses all of a sudden and she was never like that initially. I've only had her 2 months though.. She's very against people touching her tummy at times, whereas others she'll lie and wait for you to rub her tummy and loves it, purring and even nudging if you stop. Then all of a sudden, she bites and apologetically licks.. She's also started yeowling at the ceiling sometimes in different places. She grooms all the time to the point where she has little areas where her hair is thinning and has pulled out 1 tiny pea-size area of hair on her chin (she scratches it a lot which I think did it). She has no fleas or bugs on her although she used to have before I got her, she was riddled! So i'm not sure if that's an OCD/behavioural thing? She also, for the first time, started attacking the mirror in my room - now she's been used to it for 2 months always in my room, seeing herself etc. She's never bothered with it, other than looking at it sometimes. She's even slept in front of it. Two days ago, she started pawing at it and then batting it. No hissing/growling though. I have feliway in the home to help with the grooming as I suspect it's an OCD thing as there's nothing stressful I can think of, other than me leaving for work? It's made no difference though. I guess I'm starting to get worried and I don't think it's normal, at least for her, as she's normally super affectionate and while she's still playful there's this aggression that almost takes over and even she doesn't seem to know why.. anyone got any suggestions??