...When He Noticed Me...?

I know this story probably isn't unique, but here goes anyway. I've worked at the same coffee shop for a few years now, and there's this one guy who comes in every morning around 8:30 am. He’s always got his laptop out and looks pretty serious, often with headphones on listening to music or podcasts while he works on whatever project he has going. ... I've been meaning to talk to him for so long... I mean, it's not like we don't acknowledge each other. We say hi every day, maybe small talk if there's a break in his work session or something. But that’s all, you know? He always seems to be in the middle of something important when I’m at my station behind the counter. For months now, he's been coming more and more often on lunch breaks too, and it was last week when something finally happened... It was a particularly busy day, one of those days where every table is filled with people ordering drinks and snacks. I had two customers waiting in line at my till, and this guy walked right up to me, laptop still clutched in his hand. "Hi there," he said, smiling for the first time since I've known him here. "I was wondering if you have any recommendations? I usually get a mocha latte but thought it might be nice to switch things up today." His smile lit up everything around us, and suddenly the stress of my day seemed so small in comparison... Then he handed me his order and walked back over to the counter where all the cups are set out. While making his drink I just kept staring at him, wondering if I should say anything... I finished pouring and gave it to him with a little more enthusiasm than normal: "Your usual mocha latte. Enjoy!" ... That's when he looked right back at me and said something that knocked the breath out of me: “Thanks. You know, you always make such an effort here to help people out; I was wondering if maybe we could exchange numbers? So you could...you know, give recommendations or just talk sometimes?” I didn't expect it at all! But now my heart is beating so fast and I'm second-guessing everything. Was he making small talk, really flirting with me, or did he genuinely want to stay friends and get to know me better? And if we do start talking more... will that change our regular coffee shop dynamic for the worse? So, Am I the asshole here for not immediately saying yes? Or am I playing this all wrong in my head? Let me know what you think. ...