If a guy says that he is okay, does it really mean that he’s okay?

I texted my guy friend to see how’s he doing and after 12 hours of waiting he replied that he is okay. I asked if there’s something wrong and if he needs to talk, and he just ignored me again until now. I am worried about him and confused if he is fine or if he’s hiding something or just doesn’t want to talk at all.
If a guy says that he is okay, does it really mean that he’s okay?
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