Dude's are extremely emotional, they are just boss as fuck at hiding it. I think his feeling's are hurt, don't worry he'll bounce back. Dude's have crappy timing
I do this. But only if I'm busy or I don't want to talk to the person but I'm too afraid of getting them mad at me that I don't want to be rude and be like "Can you stop talking to me?"
I think that's what it is mostly. They're ticked or bummed at you for whatever reason but they don't want to get on your bad side/start a fight so they is the closest they can come to sounding pissed without thinking you'll flip shit.
If I'm sending replies like that, I just keep doing it until the person finally gets bored of the one word answers and finally leaves me alone. Or if I'm replying to messages like this, I'll reply normally until they send me a reply that basically consists of "lol," "yeah," or "k." and then I drop them like a nuke because if you can't be bothered to give me a real reply then obviously you don't want to talk to me that bad which obviously means this conversation is over.
When people answer me, "K" or "Mhm" or "Nice" I just stop replying or reply with one word answers also. If you're the only one trying, it's not even worth it. Unless you know they're busy and can't pull of more than one word answers.
You always have me, Jammy. Your lesbian Jamaican girlfriend.