Resigning too early Cuz you lost your Queen!!?

I have lost my Queen a couple times, once due to a mind blank got my queen trapped, was a pawn up but was able to grab a Rook, of course its not enough a Rook and pawn and it took some generosity play from my opponent for me to grind out the win? And recently lost my queen after grabbing a knight fork picking up a Rook and forgetting my queen was on pre?? i played on and my opponent started placing his bishops inside my pawn chain so I closed off there escape and he had to give up both bishops for two pawns, giving me a Rook,and two bishops, my opponent was none too appreciative of course these are players rated between 12--1300 rating!!?