Hey Sadie--
Sorry to hear you're not doing so well.
I was prescribed Effexor by my doctor for general anxiety disorder a couple years ago. I, too, thought this was strange since Effexor is normally used as an anti-depressant. It definitely sounds like you're dealing with anxiety (panic attacks are not a normal symptom of depression).
Personally, Effexor didn't help me AT ALL. It did nothing but make me feel sedated, it dilated my pupils really big (which I didn't like because I always looked like I was ON something), made me nauseated, tired & sluggish. These symptoms did not go away for me. They were bothersome to say the least & since Effexor did NOTHING to help my anxiety I decided to go off of it.
Next I tried Paxil which seemed to work better. Also, from what my doctor told me, Effexor is very potent stuff and is easy to OD on. Paxil is much easier on the body & that eased my mind! Also, remember not to drink ANY alcohol at all (if you do drink) while taking Effexor. This can lead to seizures & death.
Good Luck & Take Care