Hi, I started using the noctura 400 last week and I'm so tired. It seems to be making me really tired. Ive never had a problem with sleep, find the mask comfortable but a few times in the night I'll wake up and on seeing the light I'll panic as think it's already morning. Last few nights i wake up but feel like I've not actually slept ( managed 2 hours with it last night and 4 hours the night before). Prob 5 hours average per night the previous 4 days. I spoke to the outside clinic but they said just persevere. Has anyone had the same problem and overcome it? Any tips? Thanks.