Just wondering if anyone else has experienced this...

My 4 year old son was playing Mario kart with me and 2 of my friends, and randomly started BALLING his eyes out. He wouldn't tell me what's wrong, but he does that sometimes if he has diarrhea and he's just embarrassed to say it. So I brought him to the toilet and sat him down, and he didn't poop at all, but he was gassy and farted a lot. Sorry, I know, a lot of TMI. But he started crying like that again and told me that he can't see, then stopped crying a couple minutes later. I asked him, did it go black or was everything just blurry? And he replied "it was blurry, but im fine now." After that whole ordeal, he decided he wanted to go to bed early which is SUPER strange for him to do, especially since we have friends over. Well now he's laying in bed but I'm freaking out. He feels kinda warm but it might be from crying so much, but my friends are on their way to get a thermometer so I can check for a fever. Anyone else deal with this? I don't know if I'm overreacting or anything. This has happened once before too, when he's started crying because he "couldn't see".