Dilemma, what should I do?

[Harti]

It depends. Did you face that opponent often? Are they kind or a douche? How likely will you be paired against them after you took advantage? Do you care for your image? How important is that game? Are you on a winning streak and feel like this could be your promotion? Are they in a higher league even?

These are questions that could relieve your remorse a little.

I'd maybe already have conceded the turn before that just to save myself the precious time. I'm not sure how I'd react in that particular situation, though. Were it a game in a tournament, I'd probably carelessly abuse the situation (unless I care for the opponent).