My work shift is a five-day on, four-day off rotating shift. I have run into this problem a few times. My work hours are such that I could only attend the 7:30 A.M. Mass at my parish on Sunday. I had already worked my five days and was scheduled (not volunteered) a sixth day (Sunday). Not to mention that I worked an additional eight to ten hours of overtime already this week. I missed Mass in part because I was tired. The next Mass was 9:30 a.m., and I could not attend it without being late for work. I missed Mass, but not with the attitude of defiance to Jesus. Does this require me to go to confession?
If your employer requires you to work during the time that you could fulfill your Sunday obligation, or if you are exhausted and unable to attend Mass as a result, then these are sufficient reasons, just as being sick or having to take care of children are. In such cases you do not have a Sunday obligation and you do not need to go to confession. You are not sinning.