If it were any other situation he'd be going to the hospital immediately. That's definitely either a stroke or a seizure and he needs a CT or MRI ASAP.

However, the optics of him freezing like that and then getting rushed to the hospital are bad, even worse than him looking like a wax sculpture and freezing, so he came back to say he's okay. Then he goes to the hospital, but they drive him around the block a few times before arriving to throw off the press.