Sore nipples/low supply

My baby is 9 days old and we have had a rough start on breastfeeding.

She would go 5-6 hours without eating for a couple days. She was fussy and hungry but refused to latch.

Now we are back on a “normal” schedule of every 1-3 hours but my nipples are soooo sore and my supply has dwindled to close to nothing.

I am using a nipple shield and that helps a little with the pain bit not much. I am also having to supplement with formula.

What can I do to get my supply up and not have my nipples so sore? I’m wondering if part of my low supply is the fact it hurts so bad to nurse.

I’m open to any and all suggestions.