From searching the web, I liked this advice:
If it looks good to you, and captures something you like, thenAnd here's a good one:
don't worry about it.
There is a famous story about a famous photographer who did a portrait of the famous Marilyn Monroe. In his excitement he cut off the top of her head. When he apologized to her she said, "Don't worry. Everyone knows I have a top to my head. No one will miss it.And here's the photo that got me started: