I started playing and at first my opponent waited for around 15 minutes. After that he started playing. However, he didn't seem to only play better than me but he also seemed to play somehow different than other players.

And then he lost on time.

Here is a game we played.

I am not accusing him. I just wonder. At first he waited 15 minutes, which is probably enough time to use some software. And then his moves felt unusual, at least to me.

And then he lost on time. Keep in mind we played a game where each player has 30 minutes.

What do you think?

You could have at least put "NN" instead of his username.

      ATTENTION ALL USERS. THERE IS A CHEATER FORUM TO DISCUSS THESE THINGS.     

I have detected an engine user, please ban me admins                                      

Why can't you figure out how to thwart malicious disconnectors?                            Disconnectors               players letting time run out

I changed his username to NN.

I'm going to go out on a limb and say no.

       http://www.chess.com/forum/view/fun-with-chess/how-to-prevent-using-engine-and-cheating                                                                                         http://www.chess.com/forum/view/general/caruana-was-most-certainly-cheating                                                                                                            http://www.chess.com/forum/view/general/is-it-really-that-easy                                                                                                                                         http://www.chess.com/forum/view/livechess/cheating-accusation                                    http://www.chess.com/forum/view/help-support/accused-of-cheating-by-chesscom-auto-message-but-i-didnt-cheat

I see white likes the stonewall attack too*

-Just Speculating*

Thank you. From what you told me, I will assume it was a fair game. I just wanted to be sure.

I agree with you, 100%. Even if he started off using a program to help him win and when he saw that he had the upper advantage, towards the end, maybe he stopped the program, thinking that he could then, just wipe the board up with you, but by then, time, wasn't on his side. 

Yes, he would have won if he had used an engine. People with engine play like 2500 at least and don't lose even in 3 min game. Most likely you would have lost very quickly in that case. 15-minute delay doesn't prove anything at all. Do you think he started game and set up inititial position 15 minutes? Why?

Even if he did cheat, why does it matter? He lost and failed to cheat properly. You probably wont play him again for maybe the rest of your life