Please Help Me!!!

You are the adult. Be consistant, follow through, and stand your ground. Make sure that you're doing time out properly and following through everytime with it. One warning, then she gets put in time out if she does it again, tell her why she is there, then she has to sit there for four minutes. (One minute for every year she is) If she gets up put her back again telling her it is a time out, then every time after that without saying anything. Her time does not start until she sits there like she is supposed to, it is reset everytime she gets up.

You could try taking her favorite things away if she refuses to listen. "You are not allowed to play with your barbies for the rest of the day because you didn't do as I asked." If she refuses to put away toys then she gets then taken away.

When she points her finger just act like she isn't asking for anything. Tell her when she speaks and tells you want she wants then you'll answer her. Don't let her get away with pointing and getting what she wants.

When you tell her to pick up her room, tell her she has __ amount of time to pick up her room. If after that time she hasn't she looses the toys. Put them away or donate them to a charity. Your choice. Personally my DD has so many toys that I just donate them if she refuses to pick up her room.

Consistancy is ALWAYS key. I really can't stress it enough. If you tell her your going to do something, follow through.

I'd get her in for a physical with the doctor. these can be signs of a hearing situation or something else possibly wrong.
The fact that it's something new makes me wonder all the more. It may just be a phase, and if that turns out to be the case, then wonderful.
but if not, I think the sooner you know the better.