DS is 4 weeks old and feeding has become a bit if a nightmare. He seemed fine at first, then I developed a milk blister due to poor latch and/or thrush. I had to stop feeding from my left breast, it hurt so much.
I've treatment for the thrush, but the right nipple got sore as well. I expressed and bottlefed along with the occasional painful feed on the right side. The expressing along with having to deal with the thrush (and a sick toddler) was way too much to handle.
So on Saturday, as a last ditch "if this doesn't work I'm stopping" plan, I bought nipple shields. They were fab and have enabled me to feed direct from the breast on both sides. However, on Sunday and today, he has fed almost constantly all day. He falls asleep at the breast, and wakes up five minutes later, screaming for milk.
I tried him just on the breast without the shield this evening, and he fed fine, but later in the evening, he just wouldn't latch at all. He was screaming, which probably didn't help. I've ended up giving him formula, which ^he troughed because I'm so knackered, I just need a break. I've expressed some to make up for it.
So now I'm wondering:
Have I knackered my supply by expressing/bottle feeding/nipple shields (this all started on Thursday)
Has he got nipple confusion, or was is it possible that ^he was just too upset to latch?
Is there a four week growth spurt? Could the constant feeding be that?
I've had a fucking shitty week and I just want to feed my baby without worrying about latch/thrush/supply/expressing 
Sorry it's a bit rambly.