Maybe try to take more naps during the day. For me I lie on the bed most of the time with my small tv (hp) lol... sometimes just doze off on & off.. wake up drink gatorade became my daily routine. I felt better to lie abt 60° elevated using pillows to support my back and bolster support my legs.
What is ur sleeping style now? Lie flat or semi sitting position?
Anything that u like to do but haven got the chance while in school? Or divert ur attention to think of innovative ways for ur upcoming lesson observation?
search for interesting teaching tools or think of games tt can engage the students for tt particular topic?