Tell me if I'm wrong?

I've been snapchatting/texting one of my friends from school. He's a senior and I'm a sophomore. We've both been flirting back and forth and he's asked me to lunch a couple times too. We weren't official, but I thought we definitely had a connection? He's not a fboy. He's nerdy, sweet, and thoughtful. Prom came around and apparently he had told one of our mutual friends he was going to ask someone and everyone immediately thought it was me. I got a message from him later telling me he was going to ask a girl, and then that he asked the other girl and now has a date to prom. Was I wrong this entire time? Or did he just not want to pay the added fee of asking a sophomore.