Welcome to special needs, and MDC.
I an an Aspie myself, and so is my son, and many of my family members. We are each different, but when it comes to tempers and frustration we are all pretty easy once you crack the code:
Protein - All of us get grouchy when we are overly hungry, and for us nothing works quicker than protein... Hot dogs, chicken nuggets, peanut butter, and cheese are among our favorite quick fixes.
Sleep - if the sleep is awful, the day is awful....