Long covid and insomnia, any advice?

I caught covid in august of this year, and I have been suffering from extreme dizziness, head rushes, racing heart, and heart palpitations. Over the past three months my symptoms have slightly improved but only when I am awake and active.

Every night when I try to sleep once I lay down my body experiences what I can best describe as "surges" where my heart just cannot stop pounding and I get extremely powerful rushes of lightheadedness that make it basically impossible to sleep. I currently take 20mg of propranolol which helps but not enough to allow me to sleep. I'm currently scheduled to see my doctor to see if an increase is needed, though in the mean time I'm asking around for any advice because this is genuinely destroying my life.