Does Anyone Feel This Way And Does Prozac Work?

I'm 30yrs old and I started to get panic attacks about 3 months ago. Had about 3 of them, 2 that landed me in the hospital. After the doctors at the hospital made me think I was crazy because they couldnt find anything wrong with me I finally made a doctor's appt. The doctor listened to things that were going on in my life and said I had gad. He handed me samples of effexor xr and away I went. When I came home the first thing I did was searching the net to see what side effects the effexor had. Big mistake! I found everything bad about the pill and then made a decision not to take them. I continued to take the xanax when needed but tried to get through days without them. Its been 5 weeks since and now im getting physical symptoms: (pressure in my head, jaw feels tight, cramps in stomach, and empty feeling inside, unexplainable feelings). Went to another doc today to get a second opionion and told him all of my mental and physical symptoms. He said that if I wanted to take the effexor that would be fine but it might give me some anxiety where the prozac wont. He assures me that everyone is different on any medications and that all meds have nasty side effects that ppl dont normally see. Has anyone had these feelings, physically or mentally and did the prozac work? Thank you for your time to read this sorry for the length. :d