Gravity?

Marc was walking through the park when it happened. He discovered how Newton felt.
Bonk.
"Ouch!" he shouted and glared at the large pine cone that had just dented his skull.
"If only gravity would malfunction just before things like that happend" he said.
He was continuing his walk along the path when suddenly he flew upward, and smacked his head into a pine cone.
"I suppose I asked for that." he moaned.