Guy's Behavior

Signs a guy is holding a grudge?

I have a feeling an old guy friend is holding a grudge from something that happened a couple years ago.
He had a big crush on me and I rejected him in a sorta mean way but didn't mean to (a girl that liked him confronted me when she knew he was in the other room and could easily hear. It's a long story)
We recently ran into each other and have hung out a couple times and the last time, I felt like we really clicked like we used to. When we had dinner last week, he said he wanted to take a couple days off for my birthday in a month and that we should hang out. But he never texts me first (only once) and replies with short answers, although he does reply quickly. I know it's not that he's busy because he always texts me like that. I asked him the other day if he wanted to meet up at this thing downtown and he said, "I might not be able to this week but maybe other weeks" which sounds like a polite no. Why would he go from taking time off for my birthday to vaguely saying no to hanging out (within a span of a few days)? I think that how we ended things bothers him because at first he claimed to not even remember what happened, but then told me that it was abrupt, unexpected and left him with more questions than answers and that he likes to not think about it. I've had people say maybe he's still angry and holding a grudge, but when I apologized for what happened, he said that I had to get those girls off me somehow and that they were the ones that started it and should have minded their own business. I don't know how approach this or how to ask if he's angry. He's shy I should add.
Because of him telling me he was busy and being weird when we text, I texted him saying "I'm gonna give you some space haha" adding the haha to lighten it and he said "Haha wutevs". I know he can get a little immature when mad (back in high school he'd ignore me) and he doesn't usually spelled whatever like that.
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+1 y
after he said that, I asked, "What?" and he said "I don't know" so I told him I felt tired of texting him first and it made me feel pushy and he said, "No you're good". I told him I was leaving the ball in his court and I haven't heard from him since (5 days ago).
He told me I was pretty and seemed happy when we saw each other so I don't know what's going on. A friend said maybe he thinks I'll hurt him again?
Is he holding a grudge?
Updates
+1 y
Another thing, I asked if there was anyone he was interested in and he said something to the effect of (can't remember exact words) that he wasn't letting himself like anyone because he didn't want to get desperate again
Signs a guy is holding a grudge?
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