About sun turning into the moon dreams can be just really random sometimes, but maybe you were thinking about nighttime at that moment? As for the dream control, you need to be confident and actually expect it to happen to be successful, be sure to check out Dream Control Tutorial - Lucid Dreaming - Dream Views !
Also to add to what zoth00 said about reality checking, emotions can help with that too. Like thinking, 'Wow, am i dreaming?' and really expecting reality check to work.