You provide a good example of why a person should NOT confess a crush over text. You can't observe the other person's response or even tell sometimes if they're receiving your communication. In your case, neither one of you knows the real truth of how the other feels. He may think you have a cruel streak with your "pranking," but you've actually LIED to him too. Jeez.
With him ignoring you, there are all kinds of possible reasons for it, ranging from disinterest to anxiety to distraction. If you handled this conversation in person, then yes, you'd risk an awkward rejection face-to-face, but you'd be able to see his behavior and gauge for yourself how he was responding to what you were saying. You'd know for certain.
As far as handling it from here, your friendship is suffering from trust issues now because of your "prank." You have a couple of options:
1) clear the air entirely and be honest (ask for a "reset") then work on rebuilding trust
2) more or less abandon the friendship since trust is gone between you
3) abandon the crush but be just friends -- act as nothing happened.
Don't let his awkwardness be yours. You decide what you want then have the appropriate conversation. I think you know what to do.