I started having decreased sleep and feeling euphoric, is this a problem?

Possibly. If you: Have euphoric mood, marked ^ in energy level, feel refreshed after little sleep, rapid thoughts, ^ productivity, ^ impulsivity, rapid speech - these could be symptoms of hypomania or mania. If this description fits you, please seek prompt medical attention. A psychiatrist would be a good place to start. If you find that your life has spun out of control then please get care at an emergency room.