With behavior disorder, he'll have a much harder time cooperating, of course, and his triggers will be harder for both of you to avoid. But if he's having these events regularly, and he tends not to have them at school, it suggests (1) they have techniques that take his needs, patterns, and likely triggers into account; and (2) he feels more relaxed and able to let loose with you.
So you might ask if there are any specific techniques that his teachers use that you could make use of, too.
And you could try some things that often help with hair-trigger children. One of the biggies is empathy. Based on your story, I wonder if your son would have reacted this way, if, instead of "Wait a bit, I'm busy," you had given him a big smile, a hug, and a positive message, "Oh, you'd like eggs today. Good, I'll make you some pretty quick. Would you enjoy a glass of milk while you're waiting?" This would have taken an extra minute, which might have side-stepped his negative mood and saved both of you many frustrated minutes in the long run.
Parenting requires a great deal of creative problem solving and imagination and planning ahead. It all seems like so much work, but waiting until the problem has already arisen is even more work.
There are now wonderful and positive resources available for parents of "sensitive" or "spirited" kids. Books like:
The Explosive Child;
Raising Your Spirited Child;
Parenting the Strong-Willed Child: The clinically proven five-week program for parents of two- to six-year-olds:
Raising an Emotionally Intelligent Child by John Gottman;
Or google Emotion Coaching, for lots of useful information. (Here's one good link to get you started: http://www.education.com/reference/article/important-pare... .)
I hope you'll try adding Omega-3 fatty acids (fish oil is one good soure) to your son's diet – this can really help calm and normalize brain function. Also, a very large and well-controlled British study a couple of years ago confirmed that not only several common food colors (two of which are banned in the U.S.), but also the preservative sodium benzoate makes some kids measurably more reactive. See a report here: http://www.consumerhealthreviews.com/articles/GeneralHeal...
One other thought is that he may have other sensitivities/allergies that make him physically or mentally uncomfortable and hard to please. He might be sending out signals for help but have no real idea why, if he's just always at odds with his own body. Keep an eye out for possible food allergies, which can occur at any time.
I have severe chemical sensitivities, and get both physical and emotional symptoms to exposures to perfumed toiletries, home cleaning products, fabric softeners and air "fresheners." In group testing situations, I have watched children go from contentedly coloring to bouncing off walls, screaming, crying, or being impossibly stubborn just minutes after having drops of some dilute solution squirted under their tongues.
As work-intensive as it all sounds, it would be worth checking out if other fixes don't have much effect. It could actually save you untold stress in the long run. You can try sealing all suspicious products in plastic bags and using baking soda or vinegar for most cleaning for the next 2-3 weeks, and watch for any improvements in your son. If reintroducing the products (many of which are toxic, anyway) back into the home then results in worse behavior, you'll have one possible solution to work on.
My best to you. I've had close friends with highly-reactive children, and it is demanding.