In the mean time, the tops of all the trees turned orange. As if the Sun tipped over while setting, spilling blazing orange paint over the evergreens on the hillside. I started running home, afraid of what was happening, orange spreading to more trees, no longer evergreen. Scared and fascinated, I glanced back. The trees, were green again with not a spot of orange on them. I stared, certain of what I saw, trying to make sense of it.
There's an odd mystery to this piece, to the point that the simile used could quite possibly have actually happened, given the ending of the story. (It's a beautiful simile, by the way!) How can you as a writer show the reader that the narrator is "scared and fascinated" with scene description? Perhaps picking up the pace and running, glancing back the whole time, is a start?
Nitpicky: I'm a fan of active verbs rather than passive ("I ran home" instead of "I started running home"), but to each their own.