The mind is a strange thing sometimes. Anxiety can feed on itself and grow to proportions that seem unmanageable. The best way to manage it is to break it down to three simple steps:
1. Understand and accept that you are suffering from anxiety without trying to fight it off--simply recognize it for what it is.
2. Know that anxiety comes from fearful thoughts of what happened in the past or what might happen in the future, and have no power in the present moment.
3. Practice being in the present moment by doing something that takes all of your attention. When anxious thoughts arise recognize them for what they are and let them go. One well known activity to relieve anxiety is conscious breathing--simply pay attention to your breathe as you inhale and exhale (I am breathing out, I am breathing in, I am alive and well). Guided visualization can help too--imagine walking down a path thru the woods to a beautiful waterfall where you can float in the water at its base. These activities help to calm the mind and take it away from thinking about the past or future. Hope you feel better soon. I do know all about anxiety and panic and have had and continue to have my fair share so I empathize. Take some comfort in the fact that I have seen far worse than yours. You will be fine. You might enjoy reading, "The Power of Now" by Echart Tolle or "Journey to Peace" by Peg Crompton--available at amazon.com
Try not to be worried about your sinuses. My mom and daughter went through the same thing where it lasted more than a month and they're both fine.
It sounds like you have some health anxiety going on. Have you ever been in counseling about this?
Yes, I've been through times of little to no anxiety and then it comes back for awhile.