What kind of infection can cause intense cold?!

For the last few days I have had a very odd sensation in my right eye. It feels VERY cold, and it shifts across the eyeball. I have tried everything from flushing with saline solution to using erythromycin to trying out 4 different brands of lubricating drops. Nothing has helped.

Up until today, however, there was also absolutely no redness on the eye. It was irritated and felt very cold, yet there was no inflammation. Today there is a TINY amount of redness, barely more than normal, and I've got no idea what is going on.

I've gone to emergency, they saw nothing wrong with my eye, but that was yesterday (before the redness started to develop)

What could this be? I'm not looking for a diagnosis, I'm simply curious about bacterial infections that can give off a 'freezing' sensation.