There seems to be something very wrong with that graph. Here's something from SOBT, page 209 (it also includes a proper diagram of sleep cycles):
"The more we sleep, the less the body needs deep NREM sleep, and the more time we spend in REM sleep. Phase entrance is most likely to occur during REM sleep.
The time-space between REM phase periods appears near accurate though. Approximately 70-90 minutes after sleep onset, we enter REM for the first time of the night. REM will last 5-10 minutes (your graph appears to misrepresent this on the first cycle - anomalous/unreliable app me thinks!) and sometimes there is a brief awakening. In fact, we briefly awake many times throughout the night but typically don't remember it.
Anyway, what matters is that you are still able to enter the phase which you are. I don't think there is anything abnormal about your sleeping. Here is something to bear in mind from LaBerge's
"Exploring the World of Lucid Dreaming":
"While learning and practising lucid dreaming you should keep in mind two elaborations on this cycle: (1) the length of the REM periods increase as the night proceeds (note that SOBT concurs)
and (2) the intervals between REM periods decrease with time of night, from ninety minutes at the beginning of the night to perhaps only twenty to thirty minutes eight hours later."
I hope this helps 12padams!
Oh, here's a graph which is more like it. Notice the REM periods!

THE PHASE = waking consciousness during sleep hybridisation at 40Hz of brainwave activity conducive to lucid dreaming and autoscopy.