Resting one side

I have a severe crack on one side. Overactive letdown (getting better) and shallow nipples needing a deeper latch. 

I got conflicting opinions and one person say to tough it out it will get better. 

1. As far as the crack. They told me to rest the one side and pump it. However they weren't clear how often or how much. Maybe 2-3 Oz? Should I do it every feeding or just when I feel engorged? Every 4-6 hours? I can probably pump it for days honestly but I don't want to produce too much and live at the pump. Helpful to know is that I would only feed her one side each feeding. I'm waiting for the OB to call me back for the APNO, in the meantime I am using coconut oil. I'll rest a day or two but I plan on introducing the nipple shield. 

2. Overactive letdown. One of the reason I'm hesitate about pumping. I really don't want to increase supply at this point. Eventually I'll donate graciously. 

3. Self- latch vs putting baby on breast. This was a new thing to hear. The baby actually did great self-latching, it was obviously a bit painful until she got on. But because the nipples are sore in general I don't know if it's deep enough. So much confusion!