Who added a ? On my great move?


I was threatening check mate by a pawn moving to another square (the opponent was 500 evo so he didn't notice and went in a better move while we did a three knights opening.) But it's now a inaccuracy because the queen can get kicked? Why?
And yeah, this is my 1st win under 10 moves. Cause the next move he kicked the queen again at g4, revealing a checkmate threat in 2 moves.