How to cope with feeling 'detached'?

I have been suffering from panic attacks since the age of 11 (I am 17 now), and I have found it hard to leave the house for around a year. Various symptoms come and go, whether it be difficulty breathing or shaking and I have, to some extent, found ways to cope with these. However the symptom I find hardest to deal with is feeling 'detached' from my surroundings, I feel as though I am not there and feel as though I am going to pass out or die. It's a difficult feeling to describe, but I am desperate to find a way of how to deal with this. Any tips?

When I get an overwhelming feeling like something bad is going to happen, I mentally tell myself to stop. It's like opening a can of whoop-ass and helps stop my anxiety and panic right in its tracks. Once you give in to the bad feeling, your anxiety will go crazy. This is why it's important to try to stop it dead in its tracks and tell it that you aren't going to let it control your life! :) positive thoughts

Thank you RavenM for your reply, I think having a positive attitude and thoughts are definitely something I need to work on! :)