I’m confused

So I’ve been talking to this guy for a long time now maybe 9 months or so & we both like each other & we talk everyday but on Sunday he started acting not his usual self & would take long replying back so I asked why he was acting weird with me & he said “ I got a lot on my mind I just need time for me rn” I told him he knew he could talk to me if he ever felt stressed but that I understood & would give him space & he just said “ I know but I just don’t want to talk to no one” I once again said I understood & said I hope he was ok he never replied back to me after that,It’s been already 3 days & he hasn’t messaged me at all I’m so confused & i don’t know if I should just give him space & wait till he’s ready to message me or should I message him first?