That's awful. I don't even take 150mg. In fact I flatly refuse to take more than 50mg. There's no telling what could have happened. Doctors need to be more careful... esp the pdocs. I went to the ER once and an ER pdoc gave me anti-psychotics. By the fourth day I was practically psychotic. Homicidal. I stopped right there. And I was only at a third of the target dose.

For whatever reasons, not everyone will have the withdrawal problems. Maybe you'll be lucky. If not, keep the prozac in mind. I used it the second time I stopped Effexor and it was much easier. Unfortunately I crashed completely and had to go back to Effexor. I will probably take it forever.
If it's any consolation you've been lucky if you haven't had the brain zaps or anger/rage. And you may have but the other part is worse for you. Hang in there, it could take a while.