I am an overweight, (6'3", 250 lbs.), 55 year old man and I've been using a CPAP machine for apnea for 17 years. One week is not enough of a trial, by any means. It usually takes several months to really acclimatize, especially if you haven't been dreaming for some time, as your brain seems to want to "catch-up" and can give you some pretty strange, scary and intense dreams as it does so.
If you find the mask too uncomfortable the first thing to do is spend lots of time adjusting it. If it is blowing air into your face something is wrong - period. Failing that, try other masks. Take your pillow and insist on trying them lying down. If masks don't work try what we used to call "nasal pillows", the little device that positions an air inlet into each nostril. I went to these years ago and have found successive models better and better.
Try different pillows. I use a contoured, foam pillow with a small, flat pillow underneath for added height. Suits me fine and the exiting air doesn't hit the pillow and make any noise. I also use eye-shades, (our bedroom becomes very bright very early), that help keep stray puffs of air out of my eyes.
Mind you, CPAP doesn't help if you don't sleep for other reasons. Insomnia has too many causes to cover here, but here's what's helping me with both apnea and insomnia. First, I'm losing weight on a medically supervised eating plan high in protein, vegetables, nuts and fruit. I eat very little in the way of simple carbohydrates, (bread, potatoes, rice, etc.). I am seldom hungry; am losing 1-2 pounds a week; my waist has shrunk by 4 inches and I feel like a million bucks. Most importantly, my neck size is down over an inch. That much fat off my neck is making CPAP more effective.
With some of this new energy, I have started getting some gentle exercise. I'm just walking the dog 20 to 30 minutes 4-5 times a week. Not exactly high-intensity athletics, but it's helping reduce hunger, helping with weight loss and helping me fall asleep at night.
My blood pressure, which has been barely under control with both a diuretic and a beta-blocker, is now pretty well normal and my Dr. and I will be discussing reducing these meds soon. I expect my lipid profile to have improved as well.
I know it's the same-old advice, but exercise and good nutrition really do make a difference. I just wish I'd figured it out years ago!