Your response would be to go to the other person, confess your mistake and ask his forgiveness. Just because you would do that, does not mean that that's the same way someone else is going to respond. When the other person doesn't respond that way, you'll find that you get upset, which, of course, does hinder God's Spirit. Again, we need to take all our expectations to the Cross and allow the other person to respond as he will. God then, will direct us as to what we are to do.
Disappointment is the failure to satisfy our own self-centered presumptions and expectations.
Again, disappointment in itself is not sin. But if not caught and given to God, it, too, can lead to bitterness, resentment and depression which, of course, will again block God's Spirit in us. Disappointment is one of the emotions that I struggled with the most in my own night season. Nothing seemed to bring me down faster than allowing discouragement and disappointment into my soul. When we become disappointed, it not only strengthens our flesh, it also impedes what God wants to do in us.