I've never heard of shaking from adrenaline, but chins can have seizures for various reasons. Especially if it happened right after running around or running on the wheel it could be a drop in blood sugar. If he is young that is not uncommon and is one of the main reasons they shouldn't have a wheel until about 6 months to a year, but some adult chins over do it on wheels too and can't have them. You can also look at his diet, I know there is a lot marketed towards chins that is not safe for them at all, they should not have any sugary things like fruits, vegetables, actual sugar, or honey. Also keep in mind that things like chew sticks, the bark contains sugars and starches (which the body converts to sugar) so although unlimited wood is fine, unlimited bark is not. The cut of the hay also matters, 3rd cut timothy most chins love because it's soft and sweet, but contains a lot more sugars.
Other possible reason could be a vitamin or mineral imbalance or deficiency, chemicals in the environments (if you use any chemical cleaners, use air freshener, things like that), heat, head injury like from a fall, infection or even a tumor. If it continues and there is not obvious reason, like added sugar in the diet, and taking the wheel away and limiting playtime doesn't help a vet visit is a good idea.
