Player A casts Lightning Bolt on Player B at the beginning of Player B's turn. Player B casts Reflection on Player A. Is this allowed? According to the text of the LB Spell, that character is stunned (may do nothing apart from negating this Spell with Counterspell) for the duration of that turn. I think that since Counterspell is capitalized in the text, then only that spell can be used to negate LB. However, Reflection does say any spell that has just been cast is turned back onto that character. What is the proper resolution for this circumstance?

In my opinion lighting bolt would be cast and reflection wouldn't be able to be used.