Hang in there, and try to give your new meds time for your system to adjust. I haven't taken either of those, but I'm sure other members will be along soon with more advice and experiences.
The ER trips and sense of doom are familiar for me. When my anxiety started to really take off, I was in the ER several times a week. It is really hard for some of us to fight down those bodily sensations that try to scream "You're in trouble!" It's good that you're seeing a therapist; lots of us have benefitted from the help of professionals. One of the first things my therapist taught me is the value of deep breathing, and having practiced it during times when you're not panicked, so that it's not an extra challenge on top of a bad panic attack.
There are several books listed in the Anxiety - Panic Resource Center; you can find that link in the top right of each page on the forum. Many members have had success with the Lucinda Bassett program that babblin5 (Ross) mentioned; my therapist recommended "The Anxiety and Phobia Workbook," also listed in the resources.
If you search through older threads, you'll find discussions of agoraphobia too.
I sure hope you begin to get some relief soon.
Co-Moderator, Anxiety and Panic Forum