Is he jealous or just trying to play it off with bad remarks?

*Reposted* *Also not my question*
I asked one of my guy friends “is there something on my face?” and he stares at my face and randomly goes “no, K*** (the dude I recently had sex with) didn’t get it on your face, he got in it in your hair though” and I go “what? where?” and he goes “nowhere. I’m fucking with you.” He does know about me sleeping with him but my guy friend has a girlfriend.

Side note: He has the tendency to watch and give us these really curious squinted eyes and a perplexed look whenever I’m playfully flirting or in conversation with the guy I recently had sex with.
Updates
+1 y
Adding in, I told him how I slept with the guy, he goes “Well, I mean it isn’t really a secret. You walked in with him yesterday.” And I said “well it wasn’t yesterday when we slept together. It was Christmas!” And his response was, “that’s even worse!” I’m not really sure what he meant by his remark but I let it go. He didn’t look mad or jealous though. He always has had the tendency to nitpick at the guy I slept with. (He was my friend prior before sleeping with him)
Is he jealous or just trying to play it off with bad remarks?
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