D.K.
Hello Jessica,
I think this is a normal terrible twos thing. My daughter is almost 2 1/2 and is/was going throught the same thing. It has gotten better as time goes on and what I did is that if she tried to do something and got frustrated and threw something I would pick it up and bring it over to her and tell her we don't throw things and then I would help her with what she was trying to do and say to her, "if you need help just say please help mommy/daddy and then we will help you." That seemed to calm her down and after awhile she would ask more when she couldn't do something instead of throwing it or hitting something or someone.
I hope this helps.
D. K
Mother of 2, a 2 1/2 year old girl and a 6 month old boy.