Red says: We think in pickles. The average teenager's intelligence can be measured in pickles. Pickles stands for Pieces of Icky Cucumber Kept in a Lot of Ewwy Slime. It is a unit used to measure the miniscule amount of thought processes going on in very small bits of fluff and doubles as a snack that many find delicious for some reason I cannot fathom.

Red's pickles aside, I have a generally okay idea of how most teenagers think but have been unable to check my hypothesis because very few of the teenagers I know will let me have a poke around in their brains. Puberty and teenagerhood is a very stressful time full of a lot of really controlling emotions. If your sister is really mad at you, I suggest you try to kep out of her way. Or bug her a lot. That's what I did with my sister when she was a teenager. 

I really don't know what you mean by "life goal is to get you". I just suggest you try to keep out of her way. 

She probably just thinks she's better than she is because she's a teenager and you're not.  I also know becoming a teenager made me very moody and I needed a lot more sleep.  Don't worry, she'll get over it.