Users tend to wield the red X like weapon when in conflict with each other, which makes it difficult to gauge the intentions behind receiving one. Especially when it is not followed up with a comment. I don’t know if I upset this individual with my post or, like you said, he felt my early comment was funny and he disagreed with me being my own critic.
I find my tendency to give red X's stems from the teeny tiny icons on my phone and my fat fingers. I do try to correct it on the spot but by then have gone funny, optimistic, useful, creative before finally selecting the one I intended.