[RANT] Flat tire for the first time. Couldn't properly replace the tube yesterday and had to drive today

I wanted to go for a 40 mile bike after work today. Then I found that I had a flat tire yesterday night. Something pierced my back tire. After looking at the Youtube, I finally figured out how to remove the back wheel and the tube.

I inflated my new tube to check it's good. After much difficulty, I finally fit the tube and tire into the wheel. But, when I pumped the air again, there was again a leak. I think I pierced when I was fitting the tire back. I couldn't get time to do the whole thing again. I am just disappointed today.

I need to be better at this. Fitting the tire to the wheel was really tough !