Please figure out what CPAP machine and mask you have and put it in your profile so we can help you better.
How do you clean your CPAP equipment? Do you use distilled water in the water tank?
Think about how germs spread and CPAP equipment. For you to catch germs from the CPAP equipment, the germs have to be in the environment that the machine is in.
If someone else handles or uses the CPAP equipment, you could catch something from them. If the air in your bedroom has germs floating around, those germs could get into the CPAP, but you're breathing them anyway. Your CPAP could pick up germs from the bedside table, the floor if you drop the mask on the floor, etc. You're exposed to those germs anyway. Unless the germs are multiplying in or on the CPAP, you're not getting any extra germs. The CPAP machine doesn't force the air into your body any more than normal breathing does. Germs on the mask might get rubbed into your face somewhat.
Germs might grow in the water tank, so keep it clean, but, in theory, the germs will stay behind when the water evaporates.
Once you're infected, you have billions of that particular germ inside your body already. Even if you cough it up into the CPAP, it shouldn't affect you to get a few of your own germ back until long after you get well.
CPAP might make you a little more susceptible to infection if it dries out and irritates your throat.
CPAP is unlikely to be the cause of your infection, but just for the heck of it, clean everything really well. If you'll tell us what equipment you have, we can give you ideas how to clean and sanitize it.
One thing you can do is buy Control III disinfectant. Read the instructions. It's fairly nasty stuff until you dilute it, but the diluted solution is reasonably benign. Supplier #1
in the supplier list
and others sell it.