Go back to the basics:
Ik it sounds impossible to do or I’d be asleep rn but you must quite the racing mind literally close your eyes and just try to breath. Lie down and close your eyes for a few seconds. To go back down to baseline levels of anxiety, I’m familiar with that heart racing state that almost blinds your vision and ability to think straight. We need more solutions for getting calm and relaxed or this state of restlessness will corrode you from the inside out mentally and physically. 
Like how people use sensory deprivation tanks you must isolate your mind from the tornado of thoughts racing through it.