How do i know if i have sleep apena?

Ok i went to a cl tonight and the lady teaching said that people who sleep good hrs and yet wake up very tierd may have sleep apnea. she also said that if you don't go into deep sleep (which i think is REM) really do not get quality sleep. I can sleep for 5 to 10 hrs and i always wake up very tierd. I really do not know what to do about it. thanks