Crush added me on LinkedIn?

I sent him an email to thank him for referencing me and that i thought he was a nice, good looking guy. He kept it professional (i think he has a girlfriend cuz there's a girl in his fb picture). But couple hours later I got a request from him on LinkedIn. Is he just being professional? Or maybe wanting to stay connected in case they don't work out? Maybe im thinking too much into it. I just figured if someone flirted with me and I wasn't interested I'd stay far away as possible.
Crush added me on LinkedIn?
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