Hopefully he doesn't kill me!

So as all you lovely readers know, I have this cute, wonderful, super great boyfriend named Alex.

This is him - isn't he cute?

We have been dating for a few months, its been wonderful

A few days ago Alex and I were just together enjoying each others company when all of a sudden he said:

A: "I could stay like this forever"
M: "You'll say that to your next girlfriend too"
A: "There won't be another girlfriend"
M: "Why not?"
A: "Because I want to marry you"

This was followed by me moving away from him and then an awkward silence. 

Yep that's how I reacted when the boy I love told me that he wants to marry me.  I move away from him and just shut up.  Real mature right?

I think I hurt his feelings because after that he said he was sorry
He had to apologize to me for telling me his feelings
How sad is that? How big of a brat does that make me?

I need a lesson in how to handle it when my sweet boyfriend tells me things like that.  Can anyone help?

Because basically I dropped the ball on this one!