Hey Philp,
I'm not CosmicRose but I'm often anxious. So, I found some exercices to help me remaining calm and in peace.
Do you try visualization ? Like, find a place where you can be alone or quiet. Think about something you enjoy or make you feel peaceful. Then, create images with the most details possible and try to feel the feelings who come with these images.
Since I know how to visualize, my anxiety drop substantially and I've more energy.