What is the proper response?

12 hours of travel on the train and we are in Klamath Falls, OR. The train is stopped here for an hour or two, something to do with scheduled track repairs , however that works. David and I walked around looking for some Coke for him, but this seems to be some sort of Pepsi only zone. I'm enjoying the sun outside the train station, and an eldely gentleman comes out the door with his family. He looks at me and says 'So you,re taking the train today also?' Of course I answer 'Yes'. And then he says 'Congradulations'.

What was I supposed to say to that? 'Thanks, my Mom is so proud of me?'.or 'I know, I thought it would never happen for me?' I'm just so confused.
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