The feeling makes sense. Whenever our life is altered significantly we are going to feel worried and even panicked. I would put giving up my PMO habit up there with moving, death, loss of employment or any of the other major life change events that can really throw people for a loop. You have radically altered your life. That is frightening. Remind yourself that feeling like you do is normal and to be expected. And as bad as you feel giving up your old habit you'll feel so much worse if you go back.