To be honest, anxiety very seldom comes out of nowhere. It has a core source. Depression can be that core source, sometimes. You've been talking about how you're on a downward spiral and I think that could have a lot to do with it, presently. There are certain breathing and grounding techniques that work for me.

(Breathe with your stomach, not your chest) Inhale, 1-2-3-4. Hold, 1-2-3-4-5-6-7-8. Exhale, 1-2-3-4-5-6-7.

It's a good technique for fighting a panic attack, along with counting colors, sounds, textures and what-not around you. I also make myself a "logic list", if you will. It's a 't' chart, one side is my anxiety and the other side is compacted of logical reasoning. That helps for simple general anxiety. Ultimately, though, the goal is to find outlets and such that help you to feel safe. The safer you feel, the less anxiety can do it's damage.