I am on a Bi-Pap they should have told you how to use it. It takes a good two weeks or so to acclimate to this, it took me about that myself. Once you get through a month you will be okay and should be feeling better about it.

I'm a trying to be ex smoker, but makes my anxiety go up then I smoke again

The company that provided the bi-pap should be able to give you instructions on using the machine according to your doc's prescription. If they can't or won't, tell your doc and make arrangements for another DME to provide the equipment.

The hardest part is Relaxing and allowing the machine to OFFSET your breathing patterns. It is very intimidating to have your face fully covered with the mask. My trick is to Exhale harder if possible every few cycles. The machine is designed to create a similar pattern while you keep.

Between 4 - 5 hours total usage overnight is a normal prescription for insurance coverage. During the day is allowed also. You can always stop and take a break if it is overwhelming. No harm will be done. be Well.

Oh that's probably why most of us ex-smokers didn't quit sooner.