Should I be worried? Has this happened to you?

I only sleep for five to six hours a night. (It keeps getting lower) I used to sleep for seven to eight hours a few months ago. It all started a month and a half ago when I started sleeping at 12 am and set my alarm to five am. I guess my body is used to it and I never go to sleep until ten to eleven pm. Then I wake up at four to five am even without my alarm.

Im not tired right now even though it's just been five hours, I'm just really worried. Why does my body naturally wake me up after so little? Should I go to the doctor? How do I start sleeping longer again?
Should I be worried? Has this happened to you?
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