How much should I trust my Misfit Shine sleep tracker?

It has been 9 months since my VSG, and I've lost 130 pounds pre- and post-op. I still need to lose 110 pounds. I don't want to do a sleep study until I've lost at least forty more pounds. I learned I had sleep apnea in 2011, and have been very good about using the CPAP until recently. Now, some nights I push the mask off about halfway through the night because it is really bothering me and making it difficult to sleep. I've been using the Misfit Shine, and the sleep tracker shows a similar amount of deep sleep with or without the machine. 

Now, I know it is stupid to self-diagnose something this important, but I can't help thinking that the sleep tracker shouldn't show long periods of deep sleep if I'm waking up to breathe. Does anyone else have any experience with this?