Why did this guy look at me like he was stunned?

Sadly it may be the last time I see him

Yeah I agree 100% but its gna be on my mind for a while, because you're right moments like these doesn't happen very often and you feel very good when it does happen!

I've never met this guy before but at work he was talking to my coworker and I was sitting next to her. Then he shifted his gaze towards me and looked right into me for a good few seconds. I held his gaze then looked right away because I started to feel hot. He's an Indian looking guy but has the most beautiful green eyes which looks striking against his dark skin. Anyway I felt like when we both locked eyes it was as if no one else existed in the room. I don't have a crush on him but the moment was really intense. His eyebrows were lowered like he was really stunned.

OP, if his stare was intense he may be a potential psychopath/sociopath/malignant narcissist, especially if he doesn't smile a lot.
If he gave you a Christian Grey vibe run my dear, run! Run as fast as you can because that is trouble

Wow never thought about it that way...it's quite scary when you think about it. I'm used to holding a guy's gaze, coz I find it challenging. I don't think I would be getting such vibes if I had looked away.