Okay, OP here just to quickly tell you guys, I might have done the insane. I told him I couldn't make it today or tomorrow and said I'd let him know maybe later about next week.
It's true that I can't make it tomorrow, but it's not true that I couldn't make it today. It's just that... I felt scared of over-exposing my own eagerness. Of making myself too available, I guess?
I suppose the ball's back in my court now. What should I do with it?