I return to work in 2 weeks (baby girl will be 12 weeks). I currently pump once a day after her 2 am feeding (because it's the only time she sleeps after eating and I can since I don't have help). I het 5 oz a session combined. Is that enough for now or should I increase the number of sessions, and do I have to continue once I'm at work? I work 3 12 hr shifts a week and plan to pump 3x day at work. Thanks!