Terrible Twos are Here!

Well we have defiantly entered the terrible twos! I guess we have been lucky and Grayson waited until the girls were older before he started, but my child has most defiantly been taken over by something! We are having problems every night with bed time, Grayson has always been so easy, we would just put him in bed and he would stay in his bed until we got him in the morning. Even when we switched to a toddler bed, but these days he immediately gets out of his bed and comes out of his room. I know part of it is being scared and having bad dreams, but we can't just let him get in our bed every night. Can We? He also now screams at us when he does not get his way or like what we say, so he is spending more and more time in time out. It's like Drew said, Grayson has always been such an easy child that his rebellion just takes us by such surprise. It really is like something has taken over my sweet boys body and I know he does not have as much control over it as we might think. So if anyone has any wisdom how to get my child to go down in his bed at night instead of Drew and I taking turns until midnight when he finally passes out from being so sleepy(this is also part of our problem with the screaming) we will welcome your suggestions!