what happened

So I was talking to a guy I met at work.

We were talking for a little over a week- he was consistently calling and texting during that time. I would also reciprocate. Fast forward to a week after that. We messaged on Monday of last week, but he said he was at work and he didn’t call at his usual time. no biggie. the following day, I heard nothing from him. no call, no text. the day after that was the same thing. In my head I was thinking he lost interest or something so best to leave it alone. Against my better judgment, I messaged him, he said he was good and he was tied up at work but he would call me later that day. He did no such thing.

The following day I saw him at work, he said hi to me but then was trying to have a conversation, I didn’t entertain it. Later that day I saw him again and he was doing the same thing, my response was the same. He later called me, I missed the call and didn’t call him back till 2 days later. In all honesty I was thinking if it even made sense to call him back. When I did call back, we didn’t talk for long, he said he would call me back again. of course he didn’t call back. the following day I blocked him. But I am seriously trying to understand what happened cause this honestly struck me out of nowhere. and I think I have been ruminating on it because I dont know exactly what happened. what do you guys think?