According to my sleep study... I go into REM sleep approximately 3-5 seconds after stage 1 sleep. I rarely go into stage 4 sleep and if I do it isn't for long. It's hard to get through a day, even with tons of naps, when your brain never goes through the process of restoring energy and brain tissue growth and repair. So yes I sleep too much but none of it actually helps me feel that much better.
Establishing a Sleep Routine: Tips for Better Sleep