What Happened To His Eye?! (Pictures)

When I came home last night I fed my cat Leo, and he was completely fine. I left him alone for about two hours while I did stuff around the house then when I came up to my bedroom he was on my bed sleeping. He woke up to the sound of my walking in but I noticed something strange. His right eye was open but his left eye seemed to be half shut from the outer corner. Seeing that really freaked me out. It seemed like he kept trying to open that eye fully and at one point he was rubbing his eye quite hard then he laid down and went back to sleep. When his left eye closed I noticed water coming from it. His eye was like that for about 10 minutes and I went downstairs to call my brother and by the time we came back to check on him his eye was fully open. I did notice his eye looked a bit swollen and the whites were a bit pink and he kept winking/squinting that one eye. He seemed to be fine he's been playing and eating normally. For now I'm just monitoring him since he seems to be getting better, he just keeps winking that one eye. Any thoughts?

This is what I found him like, but now that eye is fully open:

He may have a minor infection or an irritant in his eye.  He should see a vet.

I would say he has some kind of minor irritant in his eye. Something like when we get an eyelash in our eye. If it doesn't wash out by itself, definitely see a vet on Monday.

I've seen this on so many kitties, including my own. Is there any hard lump around the eye? Chances are, he either scratched around the eye or got something in it. If it doesn't clear up in a few days, or worsens/becomes red and oozes pus, take to vet asap. I just had my boy have a weird black spot appear on his lower lid---turned out to be a pimple. Gotta love random strange cat things