Muth vs Mimchi Game #1

In this game, I had 1:01 left on my clock from 1:25. My opponent had 0:26 minutes left. The whole game went by so slowly because my opponent would think forever before he made a move! I felt uneasy because I never play the Nimzo, and since I was in unfamiliar territories, I didn't know all the motifs. I offered a draw after 21...Bxg2, but it was declined by my opponent. During the game, I drank two bottles of water and took small walks around to look at the other games. I also "listened to the sound in my ears". It really helps you relax! I think I should do that more often. 

In the future, I think I should only play opening systems I've prepared with, because I didn't feel like I had an advantage at any point. I sort of waited around, and since my opponent playing White did the same, we petered out into a draw. I would like to be more aggressive next game.