Tammy,
You will do fine on it. Just wanted to let you know that when I was taking Effexor XR, it made me feel hot and with activity, I would sweat more than normal...but that is a side effect of Effexor. I loved it, it did wonders for me, but it quit working after years of taking it. I don't recall any major side effects when I started taking it...and if I had them, I am certain I would have remembered!
Good luck with the med change...you will do great!
Sylk