Does my lecturer like me in that way?major heeeeelp?

okay so i have the biggest crush ever on one of my teachers at university. he is only a few years older than me and is HOT HOT. We have a really good chemistry and he is always making eye contact at me and i do the same back. But just after a cl where he is staring at me, flirting smiling at me, and talking to me, the next day he barely makes eye contact. whats up with this??? He is a really sweet, hilarious guy, and is everyone fave lecturer. Does he like me??