Going slow - as you stated maybe he was (in your first thoughts anyway) but I just have to say after one date and some online interaction it brings to question for me, whether you get attached easily and quickly? Not judging, we are all different but something I thought might be good to bring up for you to analyze about yourself. jumping in with both feet too quickly will turn away more than a few possible suitors so as advice, I'd consider whether this is a tendency of yours or not.

And so you can judge my own perspective, I know this tendency because I have been known to do it myself so i'm really not just shooting from the hip here

HOpe this helps!