Just wanted to update this in case anyone comes across it and might find it helpful. Thank you so much to everyone for the posts, I think you saved us from switching to formula.
I had bought some nipple shields when pregnant because a friend found them useful and it seemed like a sensible idea. I had forgotten about them, but posts on here reminded me and I dug them out. They are Mam ones, really soft and flexible and my baby was latching and feeding with them when she had not managed to before. It felt like a miracle, I had gotten to a point where I thought I would never be able to feed her the way I wanted to.
I also pressed re the tongue tie, as suggested on here. My baby was then diagnosed with a posterior tie, but in order to get a referral with the NHS, they have to lose so much weight for a prolonged period, that we decided to find a private specialist instead. She had lost 9% body weight by day 3, and there was no real improvement by day 5. We had the tie snipped when she was eight days old, by a wonderful lady (Wendy Birtall, in case anyone is in the east of England and unfortunately finds themselves in a similar position to us) I contacted her on a Saturday and sent photos and videos, we had a phone appt a few days later and she came and did the assessment and subsequent division on the Wednesday morning.
My baby was distraught after the division, it was like going back to square one with the frustration and upset of being unable to feed
a couple of times I had to give her to DH and go away because I seemed to upset her so much. She was so desperate to feed, and probably in pain, but just couldn't figure out how to get her little mouth to work. She had fed successfully immediately after the division, but we seemed to go backwards after that, she was just so upset it was really hard to position her well etc.
It took a good couple of days for us to get through that, but she is now breastfed and having no formula, hurrah! I am still using nipple shields. I've dreaded feeding so much, and her frustration upsets me so much that I am finding it very hard to want to upset feeding again right now. I don't think it is affecting my milk, as she is now gaining well. She was 7lbs 1oz when born, and by day 17 had made it to 7lbs 3oz. The weigh ins have been very anxiety inducing too, so I'm trying to be kind to myself and not rush into changing things again right now when the balance seems to be the best it has been.
Again, thank you so much for all the posts. I felt lost, and there were so many pointers and ideas on here that have been really helpful, including the burger hold 😁
Also, have a squishy newborn pic for good measure 🥰