Saying humans created time is like saying we created the 3 dimensions just because we made a way to measure them. Regardless of whether or not we measure it time still exists on a physical level, if there was no night or day etc. time would still exist, we would just have a hard time measuring it. What we created was a way of measuring cycles, but that doesn't negate times existence. If you had no concept of measuring time you would still recognize that there are things that happened before that aren't happening right now, hence a past, and hence time.