2 popped tires in 1 day

So on the way to work yesterday I had a popped tire. It was right before I got to the office so I didn't have to walk far. However, on the way home it was a long bike walk. I walked from my office to Twenty20 Cycling in Hampden (took about 25min). There I got a new tire and brought it home. At home I started replacing it and when I was pumping it up it exploded on me! It was so loud that the sound wave made our piano play every note. Fortunately it didn't hurt or have any permanent damage to my ears. I didn't understand what I did wrong, and still don't, but I went back to Twenty20 and got another one and tried a slightly different method of replacing it and it worked fine.