I know I harp on about this but u need a proper sleep study done, they can establish ur oxygen level, brain activity and wellbeing during all the stages of sleep.
Yes it could be sleep apnea but there are other illnesses and deseases that present in the way u state.

Dont expect a quick diagnosis as often sleep difficulties are often a precurser to other conditions.

Try for a qualified sleep study, it is worth it.

Either that or u take too much coffee.

Good Luck