Do you think this is cheating? I really want to know.
Am very confused. I have made changes but not altered nature. Have I done something wrong?
The OP used the terms "cheating" and "wrong". Those concepts only apply when applied against a set of rules/regulations/standards/laws. None of which exist universally in photography.
Now, a specific competition, website, organization... may have their own rules and they can be as restrictive or as liberal as they choose. You can only cheat/do something wrong when you try to break these rules.
Absent of any such rules or standards you are incapable of cheating or doing something wrong. People may disagree or dislike what you choose to do to that photograph and that's ok. They have a right to their opinion.
You remember what they say about the worth of an opinion -- when you put in your two cents, people will only give you a penny for your thoughts.
However, this topic raises an interesting and perhaps unanswerable question: At what point does an image cease being a photograph and become graphic art?
Identifying the extremes is pretty easy. We can all identify a picture taken with a camera with basic processing as a "photograph". We can all identify graphic art from many examples on the Internets Tubes of some pretty wild stuff. But where is the dividing line? At what point, when I am dickin (technical term) with my image in PS/LR do I cross the line from having a photograph and start creating graphic art?
Well, there is no line, or more accurately, there is no universally accepted line between photographs and graphic art. Everyone has their own internal definition of the difference between photography and graphic art. Even if people seem in agreement, it is then only a collective opinion not a standard.
So the point of my ramblings is that you were not cheating nor doing something wrong unless you were submitting this image to some entity that has some sort of rules. Of course that opens up a can o worms about implied or assumed standards, but we all know what happens when you assume something.