Some advice/guidence/understanding would be nice

A couple of years back I was sitting in the bus. While I was looking out of my window I suddenly saw a red bike parked next to a tree. About 3 meters from the tree I saw a blond lady, around the age of 40, with blood coming out of her head.

It is safe to say that the woman wasn't alive anymore. Next to her, lying on the grass, was a white helmet. I lost her out of sight for a second to tell the bus driver to stop so we could help her.

Before I reached the driver I looked back. The lady, helmet and her bike were nowhere to be found.

Could someone please tell me what exactly happened that day?

I don't know if this is of any meaning, but when I saw the lady I also heard someone whispering something in my ear. It was to vague and quiet for me to understand it.

I apologize if my English isn't all that well as it is not my native language.