Word of warning, the sleep trackers on the market are not very accurate for tracking sleep phases. Folks like Matthew Walker are pretty adamant about this. You have to measure your electric brain waves to know for sure, not approximations from heartbeat, movement, etc.

My Oura and Fitbit sometimes give wildly different sleep phase readings for the same night. Also, each will sometimes give arbitrarily unexpected readings that leave me scratching my head.

As someone mentioned, those trackers aren't that accurate.

However, if you think you don't get much deep sleep, for the love of everything, get tested for sleep apnea. A home sleep study is quick and easy if you have reasonable insurance, and if you do have apnea, getting it treated could literally change your life (or even save it).