When in doubt, go to the vet. Our four legged friends can't talk, whereas our kids can, so better to be safe than sorry, as you found out. I had a similar experience with a Lab a lot of years ago. He kept rubbing his face on the floor and with his paw. I couldn't see a thing. The vet pulled a quite large pointy seed, the kind that itch like hell on you when they get in your socks, out from under his lower eyelid.
I didn't go to the doctor for 3 days when my leg was broken in 3 places; I kept telling myself it was a sprain. I run to the vet at the first hint of a problem. Anyone who doesn't think that's "real manly" can just think it, I flat do not care.
