Has he been avoiding me? If yes, what could be the reason?

Hello!
Long story short, there's a guy I like and I have confessed my feelings to him months ago already. Things were going absolutely well for us since then (we grew more close, planned future dates, etc). But since the beginning of this month, he's acting a little different:

Recently, he's been answering to my texts late (he sees the notification but chooses to reply later). He doesn't initiate the conversation by himself anymore. And nowadays I kinda feel that he only talks to me when he feels bored and has no one else to talk to.

About him, I've known him for a long time. He doesn't seem to be the type of person to play with someone's feelings like that. He's a sweet, innocent creature because he had gone through a lot himself. But I wonder why he's been acting off with me now. Sometimes, he's interested but most of the times he answers kinda dryly.

He appreciates me, but doesn't talk often anymore? I really wonder why would he do that.

Has he been avoiding me? If yes, what could be the reason?
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