Does anyone else get anxiety that comes out of nowhere? Like, no specific trigger brought it on and there's no real intrusive thoughts that come with it, but you still feel all those physical symptoms? How do you deal with it?

Yes all the time - try to remind myself “this is just anxiety and OCD being misfired in my brain, and it will pass” usually lay down drink some water and eat soemthing sweet!

Lately, I watch "satisfying" or ASMR videos on YouTube. Sometimes looking at or listening to something soothing helps with the anxiety. Meditation can help, too. I'm sure there's a zillion guided meditations on YouTube--although you might want to look for one without ads. :P