Night shift nurse trying to conceive

We have been trying for two months to have a baby. I am a night shift nurse. I work 4 days a week.. 10 hour shifts.. From 11p-9a.. Any four days though. I'm not on a set schedule..  Has anyone else had fertility issues while working nights? I am starting to think it's impossible, and getting very frustrated. Would you guys recommend me speaking with my DON about a set schedule?