Ahhh, good times, good times. The first time I changed a tire was to switch the nobby tires on my old hybrid to smooth road tires. I was doing pretty good and was proud of my work, so I called hubby in so he could tell me what a good job I did all by myself. Well, turns out that I didn't know that certain bike tires are like car tires. Due to the tread, they have a little arrow saying which way they're supposed to roll. What are the chances that I'd put both of them on backwards? 100%. So off they came again so I could turn them around. After I got them both back on, I went in the house...and not 2 minutes later there's a loud BANG! Yep. The tube had gotten pinched and popped. I changed 5 tires total that day. By then it was too late to ride.