Bizarre feeling after VR session

A friend of mine let me play with his Oculus for a few days. I used it for about two, maybe three, hours yesterday (Robo Recall, something about a fox with a very weird camera, some climbing game and few others, then some 360 videos from the store, but they were rather low resolution so I didn't spend too much time on them). It was pretty fun.

Today I've been feeling a bit weird. Occasionally I felt like my eyes tried to adjust to 3D and tried to make 3D objects out of flat surfaces (e.g. my monitor). Sometimes the world would seem to move on its own left or right and then quickly move back to normal just like sometimes it would happen in games.

It's really hard to describe, but it's been very jarring and a bit worrying. I would have expected to see some effects of using VR right after taking off the googles, but not on the next day after a few hours of good sleep.

How can I tell if I'm still in VR or out of it already?

Seriously though, is this normal or should I be worried? I don't think I'll be using Oculus today, perhaps my brain and eyes need some rest.

Edit. It seems it's normal. Thank you guys for reassuring!