Hi Amanda, my name is Kelly and I can understand what you're going through. I often have panic attacks, particularly when I can't control the environment I'm in or when I'm subjected to rejection, particularly from my boyfriend.
Are you on any medication? I often have racing thoughts and my doctor prescribed me Seroquel, it's an anti-psychotic (I freaked out at first too, but a lot of people with bipolar take it) and it really helps you relax. I have trouble sleeping so I take mine at nightime, but in lower doses it can be taken throughout the day-it might help you.
How long have you been diagnosed with bipolar? I've been diagnosed for little over a year and it is such hard work. You feel like no one understands you and everyone is kind of "jumping down your throat" when you can't explain why you feel the way you do. This forum is a great place because everyone understands each other because we can all relate.
Please don't hesitate to contact me-I'm on Yahoo Messenger and would love to chat.