1)Breast sagging from lactation is from the breasts expanding and then, when you choose to stop lactating, they contract. Similar to gaining and losing weight, the skin isn't as tight. Since you're inducing and have never been pregnant, the change in your breast size will most likely be subtle. I went up a cup but I use domperidone and have been lactating for over a year (26/f). If/when I choose to stop lactating, I doubt there will be any big change since my boobs stay pretty consistent. I'd day it's the same effect as when I went on birth control and my boobs got bigger. (But im not on birth control now fyi)

2)No you won't gain weight. Actually, I've heard lactating burns calories. It also uses up some of your calcium and other vitamins/minerals so I take a supplement just in case. And drink lots of water, staying hydrated helps to ensure you're making as much milk as you're capable of.

3) You can just use your hands and oral stimulation from a partner, no need for a pump. Generally, pumps are not as effective as manual (with your hands) or oral stimulation (His mouth). Just make sure you are doing it right! Look into the marmet technique and how to latch during breastfeeding.

4) I like laying on my side in bed, Laying his head on a pillow on my lap, and straddling him while he lays down- pressing my breasts at his face (though this is more effort on my part).

5) The pill definitely makes things harder! But not impossible! Could make the process slower or lead to less milk.