What is your definition of psychology ?

So, my step brother took the plea. What now? What happens next? I have been preparing for the worst, and now I'm suppose to be happy? I don't understand.

Alright let me start this off with some context, I am a 18 year old senior who's life revolves around animals. At my house I have a cat and 7 reptiles (all mine), but at my grandparents who i vist every weeked, has not just a cat, but a spawn of pure evil. Now this cat we bought from a home as a kitten and raise it up to the evil it is today, it has never been abused and has a life full of enrichment amd everything it needs. But even so this cat does not let anyone pet it, it never purs, it breaks stuff, attacks at random, and has a ever growing desire to murder. My cat at home is the complete oppisite, so needless to say I was taken back by the attitude, and tried many things to correct this behavior. But recently I have had this ever burning passion to strangle the cat, step on its neck, or simply kill it in anyway possible. This started when the cat decided to ######6 fling one of my gecko enlosers across the room, break in, and eat its tail. It must have thought the taste was good too, because now she wont ######6 leave any of my enclosures alone and i have to hide them in the basement. Ever since she touched my precious child, I've felt this way, and I have given up on trying to fix whatever mental problem this cat has, because whenever I see it, I get a visual image in my mind of abusing the thing. This freaks me out, I would never hurt my other animals or even my cat, but this ######6 evil has me going crazy, and these thoughts i have need to stop.

I'm a 16 year old girl. I never bit anyone as a kid or anything like that. I have been diagnosed with OCD, Severe Clinical Depression, and a Generalized Anxiety Disorder. I am on medication for those things. But I have been having the urge to bite things lately. It doesn't matter what mood I'm in. I just randomly have the urge to bite things. I mostly bite myself; I could never bite another person. Yes, I have been self-harming for a little over 4 years, so maybe it's just another form of self-harm, but it's getting pretty bad. The bite marks last about a half hour. I've only broken through skin once. What is going on with me..why am I biting all of a sudden...

Is it abonormal that whenever I gain interest in a certain show or game that all of a sudden I drop literally all my other interests and focus mainly on one character in that series/game. It gets so bad that I'll actually imagine myself being in a relationship with them and also adopt most of not all of their traits and pretend I've always acted like that when in reality I was different before hand. But then again that could've been another character. I've been doing this for near 10 years so I don't even know who I am anymore. It's frustrating and I'm honestly concerned as it's nearly ended friendships in the past. In order to stop it, I've tryed asking myself am I doing this as me or as the character. This has proved unsuccessful as it just makes me paranoid that I'm being a character when I do something the same way I'd imagine the character doing something. It could be the most mundane task ever and I'll still be paranoid that I'm not me but someone else.