Thank you .
From your description it sounds like he had a seizure. There are several things that can cause a seizure in dogs the most common being.
* Primary idiopathic epilepsy- This usually shows up between the ages of 2&5.
* Low glucose levels
* Problems with the liver such as a liver shunt
* Eating something toxic
* Brain tumor ( more common in older dogs)
Here is additional information on causes of and treatment for seizures in dogs LINK
I would suggest having your vet take a look at him and possibly having some blood work done.In most cases no medication is given to control seizures unless they begin to happen frequently, last longer or there is more then one in a 24 hour period.
As long as he continues to do well today there is no reason to rush to the vet right away but I would call and let them know what happened and schedule and appointment. If he as another seizure in the next 24 hours then I would get him in right away.
In the future you do not want to offer food until he is back to normal as there is a risk of choking during a seizure.
As for the skin problem it sounds like there may be a secondary bacterial infection going on and this may require antibiotics to fully clear. This breed is prone to a condition called Primary acanthosis nigricans which can cause hair loss, infection and leathery skin often on the chest or groin area.I would try to prevent licking as much as possible as this will only make the problem worse.Link
I hope this helps and he continues to do ok. Please reply back if you have additional questions or concerns and I will be happy to continue.