From my understanding DSPD is like jet lag, where one cant sleep in "normal" hours, i have quite a weird schedule of sleep, to be honest, when i think about it, it has been like this for at least 2 years now, never realised how much of a problem it was, but lately i have been feeling extremely sleepy during the day (i am a highschool student, i study from around 8am to 2-4 pm).
my schedule of sleep during normal days usually goes like this: Sleep at 2-4pm till 10/11pm, then on the same day sleep at 3-4am till 7am (yes i sleep twice a day, if i dont its really hard to function the next day), because i wake up at 7am i usually feel very tired at school and its very hard to focus.
Usually at holidays or saturdays i sleep from 3pm(which i find my ideal time at noon) till 10pm and then from 3am(ideal time) till 11-1pm, if i can get this schedule i usually feel very good at morning, i can wake up without problem, i dont feel tired at all.
and these schedule have been like this for around 2 years, i usually dont miss my sleep during 4pm, because i just cant, i find myself almost everyday coming back from school and going to bed( sometimes i dont even remember to eat or do anything before). When i do try to not sleep at noon and sleep at "normal" times like 11pm-1am i either wake up at night and cant fall back asleep or i wake up very tired and i feel tired most of the day.
Im probably going to check this soon with a doctor(cant currently because im busy with school), so i decided i might as well get some answers/advice here.
Thank you very much for spending your time on reading my complaints and answers, have a great day.