It depends on the PD. I had plenty of tickets beforehand and they didn't care. In the poly they asked me if I had ever done illegal drugs. I had tried pot when in highschool but never messed with it again. That didn't hurt me either. I was told that if I lied on the poly, it was an automatic failure. The main thing is prior criminal history.
Stress isn't bad to deal with as long as you recognize it and make it a point to deal with it. It can be as easy as exercising or meditation. Just take a few minutes a day to do stress relief techniques.
I loved Midnight shift. I was home everyday and could sleep while my wife was at work at the kid was in school. I would get out of bed around 3PM and spend everyday with my kid until he went to bed. It took my wife some time getting used to being home at night alone but she did.