If Danish Gambit rejected, then how to continue the chess game?

What if your opponent rejects the Danish Gambit? Then what is the move you should play immediately to counter attack?

Below is a chess game which my opponent rejects the Danish Gambit by bringing his knight out instead of taking the pawn which I offered to him. That really makes the situation a lot more complicated than I have expected. The next move we should do if our opponent brings his knight out is to push our pawn upward and thus forced his knight to go somewhere else. Then we can have all the fun even though we have to abandon our initial plan. I did made a blunder and lost my knight during the game but I manage to come back strong and finished him up.

Don’t ever give up unless you really cannot come back anymore.