Getting a divorce and I have this knot in my chest.

As title says, I'm going through a divorce. Sometimes even when I don't have a low mood, the physical anxiety kills me. I have this knot in my chest and nothing seems to make it go away. Normally I can put the anxious energy to work and use it to work out, get chores done, get motivated and focused, do yoga, or whatever. But this knot in my chest, above my stomach and below my heart keeps me from being productive. Nothing makes it go away once it's there. I get burning hot flashes. I can deal with the emotional anxiety but this physical stuff kills my motivation and my ability to center myself and be present for my kids and for myself. Yoga doesn't work and podcasts help my mood but do nothing for the physical stuff. Any advice is welcome!