Mowin' the lawn

Today I offered to mow my dads lawn as it needed it and he's not in the best of shape to do it. He showed me how to work his riding lawn mower and off I went. I had thought that I would be using a push mower but he said it was fine to do the riding one. It was better to do it this way as I was not dressed to mow it with a push mower with flip flops on. About half way through my second time around the yard I thought to myself "This thing isn't mowing". I was quite perplexed as to what was wrong when all of the sudden I realized I hadn't put the blades down. So back to square one with the mowing.
The back yard was tricky because of it's layout. I was rounding a tall but skinny tree trying to get as close as i could when I got stuck. At first I was just caught on the branch so I decided to keep going when all of the sudden the tree bends and just as I think I'm cleared I hear a snap and the tree swings up hitting me in the back. Luckily it wasn't a hard hit. I was mortified as I thought I had ruined my dads riding mower and that I had ruined my step mom's favorite tree. I looked over at my dad and he was dying laughing. He told me not to worry everything was okay and that they were wanting to take that tree down anyway. Turned out for the best.