Most Helpful Guy
Don't be shy text him, the sky won't fall down if you contact him first. You clearly want to or you wouldn't be sharing this problem.
Most Helpful Girl
If he's switching up so quickly then something tells me he has lost interest or is occupied with someone else right now. He could possibly be dating someone else maybe on the side and now he's unsure of his feelings. It's not really normal for a guy to go really distant if he's super into you. I've never had that issue with guys who truly liked me. However it was always the players or guys who I never ended up with who flaked quickly from the start and changed all the time.