I think it's probably to do with stress, especially if you've started having panic attacks. Is there something stressing you atm or do you think that your condition might be getting a bit worse? Do you have a pdoc/T you could talk to?
I found putting on my favourite music on my ipod really loudly and focusing ONLY on that helped cos I stopped focusing on the noise and my thoughts, which was actually only getting me more wound up. Oh and taking a break, if I could, from whatever was stressing me, like a uni assignment, and trying to relax. Maybe that might help you?
*Willow*