Feeling guilty

Hi guys, So i have severe OSA and been on the pap about 7 months now. Unfortunately though i found its not that consistent and i have a few days a week im still very sleepy. so much so i literally dont drive to work cause i know its just not safe.

I have never asked for medication of any kind from a doctor before and to be honest i feel guilty even asking like the cpap should work but would i have a case for it? I honestly feel like i need something for the off days and even when i dont have the cpap. it broke down at one point for a week and that was honestly the worst week ever. it felt like my apnea got 10x worse being off the pap suddenly.

I have an appointment with my sleep specalist later today but not sure if i should be asking or not. Has anyone got and used modafinil for a similar reason?