Nipple pain!

Kelly
Hi ladies. 
I'm day 3 PP and my gorgeous girl loves the boob but she's got such a hard suck and it's hard to get a good latch before she clamps down to feed and I feel like my nipples are going to drop off. Because of this constant feeding iv been topping her up with formula but I'm wondering if maybe having a bottle in her mouth may be making her latch worse due to confusion. I don't want to stop breastfeeding but I honestly dread putting her to me. Any tips? Or any one sympathise?