Venlafaxine is a very difficult drug to withdraw from without feeling bad. I was on 150mg a day for years, and it took me months to withdraw. I know you have only been on it for a year, but I think you will still get withdrawals. It must be withdrawn from very slowly, and by small increments. I am surprised your doctor did not tell you this. This is a devil of a drug to stop.
What you are experiencing now is withdrawals. As you have stopped, I suppose you feel you cannot go back on and withdraw slowly. Hopefully going onto the other anti depressant will help, but of course, that could also make you feel shaky when you first go onto it. The withdrawals may last a time, and you will not know exactly what is causing you to feel as you do, withdrawal from one drug, starting on another, or a combination of both.
You will find a lot of posts here about withdrawing from Venlafaxine.
I wish you had got better advice from the psychiatrist about this.
Thank you for your response. My shrink told me that what i read on the internet is not true and I wouldn't have any withdrawals. I feel like crap right now.
It's on the label, for God's sake. It has a black box warning about quitting abruptly, as do all these meds, but that med is one of the worst. The only safe way to quit this drug, or any drug but especially this one, is to taper off slowly until you're off it successfully and then start a new drug. You need a new shrink. Sorry to be blunt like this, but don't expect that just because some has a degree they have any idea what they're doing -- you have to quiz them to find out. I'd go back on the Venlaxafine and off the Prozac, if it were me knowing what I know now, and taper off as slowly as you need to before switching, just to be safe. I'd also tell your shrink he or she needs an education.
Your psychiatrist should have lowered your dose of Effexor, and I know this isn't popular, but start the Prozac a few days before going off the effexor completely. Or added Clonidine with the Prozac.