Seems from a quick look you played a lot of tempo wasting moves which didn't really help your position and your opponent blundered his way into the loss. Don't really have the time right now to look properly, nor am I probably a good enough player to see everything.
Game between me and my friend

e3 then e4. Nc3 allows you to play e4 straight away or you could play it move 2. a3 to stop the knight when I'm not sure you need to. Moving your c knight 3 times just to trade looks like a waste to me. Not that you played badly, I just think there will be moves to improve your position more. Also, you gave away the bishop pair for no real compensation.
This opening I played is called the Zukertort variation of the Colle System and apparently playing e3 than e4 after I've developed a bit further is the way to go. I understand what you mean by moving my knight 3 times but I wanted to trade so I could kick his knight off f6 and form an attack from there. Also, how did I give up my bishop pair? I traded my white bishop for his knight to open a hole in his king side.
Once again thanks so much for your feedback, it's much appreciated.
Hi everyone, this is a game between me and my friend. I am white and I'd appreciate it if you could give me some constructive criticism.