Re: Milk production dropping; up all night!
It sounds like reverse cycling to me too, maybe in combination with a growth spurt. My daughter did not eat less during the day when I went back to work either, but she did start waking up several times a night to nurse. It wasn't only about food, she wanted that emotional reconnection with me. I didn't discourage it because I liked reconnecting with her, too, and I was able to cosleep so it didn't affect my sleep much. But if it's not working for you, you may find that some of the tips in the link provided above will work for you for discouraging the frequent night feedings. If all else fails, she will probably slow down on her own in a few more weeks once she is used to not being with you all day.
It is also completely normal for your production to go down throughout the day. Most women, even ones that don't pump produce more milk in the morning and decrease as the day goes on. You can increase your milk production, though. There are supplements you can take and, like Andrea suggested, you can pump more often to stimulate your breasts to produce more milk.
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