Can't Sleep

I have a busy day tomorrow and my anxiety is super high and it's keeping me awake. My heart is pounding and it feels like everything is spinning. I want to go sleep in my recliner chair to ease the heart pounding but I'm not sure if it'll work since it hasn't helped me fall asleep lately. I took extra melatonin supplements and kept myself busy and moving all day. I feel physically exhausted but my anxiety is so high that I can't fall asleep. What can I do?