Earlier Sleep–Wake Cycle
If you wake up too early in the morning, the reason behind it is not always that you have bad sleeping habits or that your thoughts are running through your head. Waking up too early can also be caused by a shift in your rhythms.
Your chronotype is unique to you. Some are more early birds rather than night owls and are more prone to waking up early in the morning. However, chronotype can change during your lifetime. Usually, your inner clock shifts towards early morning as you age, and to some, the shift can also be quite drastic. In this case, it might be that waking up earlier is just a natural part of getting older, not only a matter of other outer factors.
If your concern is that you wake up "too early," here's a little encouragement for you: It's totally fine to wake up early! If you continuously find yourself waking up energized at 4 or 5 in the morning, you can freely get out of bed and start your day. Most likely, you'll get tired earlier in the evenings the following days, and that way, your body will fix the slight sleep deprivation, and your body will get used to the earlier rhythm. By listening to your body, you can find your rhythm - everyone doesn't need to be asleep between 11 pm and 7 am.
If you take care that you go to bed early and sleep enough, there is no harm in having an earlier rhythm. However, having an earlier rhythm might make social life harder. If that seems to be an issue, you can start changing your rhythm to a later one, and the next Habit can help with that.
Example Habits to try:
Fischer, D., Lombardi, D. A., Marucci-Wellman, H., & Roenneberg, T. (2017). Chronotypes in the US – Influence of age and sex. PLoS ONE, 12(6), 1–17.
Gregory, A. (2018). Nodding Off: The Science of Sleep from Cradle to Grave. Bloomsbury Publishing.