Working out in the mornings without food

Started my new routine this morning as my work starts this week. Doing the kickboxing 2 week challenge in addition to the last day of Fitr3. My single parent work schedule is maxed out, so I am starting the workout at 5.30 am, with no food beforehand. I was scared but pushed through 45 min of workout today. Anyone else do this? I usually need my breakfast to function properly so I hope this will be possible. I am concerned that if I don't do this I will not get this time for myself.