We took her in as stray when she was about 4 or 5 months old,she is now about 4. She has always been a touch on the feisty side,which I put down to having a bit of a rough start in life. She has NEVER sat on mine,or anyone else's lap,but she is very affectionate in other ways and always greets me with numerous head bonks,drooling and kneading. But last night she attacked my leg quite badly. I was petting her and she gave me a gentle bite on the side of my hand as she frequently does,it doesn't hurt. Then she suddenly whipped round,lunged at my leg and dug her claws in,then sunk her teeth in! She wouldn't let go when I shouted at her and I had to 'scruff' her to get her off me. She then ran and hid,leaving me with a bleeding leg and several claw puntures. She was back half an hour later,all affectionate. Why on earth did she turn on me like this? She has never done this to me before. I would add that she is a mainly indoor cat (I live in a second floor flat on a busy road but with a balcony she has access to) and she has been neutered.