Is he not interested anymore, or am I overthinking it?

Anonymous
I had bad dating experience before so I always overthink and am wary about the signals someone is sending.

I’ve been dating this guy for 3 weeks and went on 3 dates so far. First one was initiated by him, other two by me but he was always pretty enthusiastic when I brought going out. He initiates conversation almost everyday, but I’m usually the one that keeps it going on text and he keeps it going when we meet up. When I text, he responds within a couple of hours max and if it takes longer than that, he’d tell me what he was busy with. He asks what I’m doing, etc when the conversation dies down. He pays for our dates (Yes, I did offer) and drives me home. He let it slip that he told his best friend about me, and said that he puts effort to text me although he doesn’t really like texting.

Although, here come the things that make me wonder whether I’m receiving mixed signals. I know he has a busy life, but he doesn’t usually initiate meeting up. I usually do that. Also, he’s not very attentive on text and would be dry sometimes (would end up restarting the convo with ‘wyd rn’ though). Also, he cut our last date short (2 and a half hours in) because he wanted to go home and sleep. Today is also our first day without talking (the last text was ‘good luck’ which I sent to him yesterday) and he didn’t initiate anything today.

Am I overthinking this? And how can I communicate effectively without scaring him away? His birthday is tomorrow, by the way.
Is he not interested anymore, or am I overthinking it?
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