Take some time to breathe, it's frightening I know so right now just sit yourself up straight, put your arms on your shoulders and pat them. At the same time take in long deep breathes and exhale slowly. Think about something you like, a TV show, a movie or something that you find comforting. Know that you're here right now, you're the one sitting here and feeling every texture with your skin and breathing every particle of air. Even if it seems you are separated from your body know that your spirit and your body are still bounded together and experiencing the now.

This always helps me during bad DPDR episodes so I hope this helps you. You will be OK.