Hi Rascal,
I hope things work out for you with the bfing. I know it is extra hard with a 'preemie' and lots of people at our neonatal unit didn't manage to bf.
Alexander was also born 9 weeks early and I have severely flat and inverted nipples too, which don't respond to cold or anything. I tried so hard and when he was 5 weeks old, just like you, resorted to a nipple shield. It seemed to be going ok and we were sent home after 3 days of feeding that way. However, after 4 days a midwife came and weighed him and he'd lost 10g, and after he'd been home a week he had just put the same 10g back on and nothing more. After the first visit, I was sitting there struggling with getting him to take the nipple shield and he was dropping asleep as usual, and I worried that I wasn't getting much milk, so I expressed and could only get 1oz. So not only was he losing weight but my milk supply was dwindling away.
What did I do? Well first of all I got some frozen milk out of my freezer stash, thawed it and gave him it in his first ever bottle. He only took 20ml of it, but I went upstairs and sobbed and sobbed about it. Then, bang on cue, my 'My Brest Friend' feeding pillow arrived in the post which only made me cry more!
I tried and tried to feed him - we even used the breastflow bottles for a few months so his latch would be the same for bottles (or as near as possible), but there came a time when the schedule of feeding, then expressing, then washing up bottles and pump bits and then feeding again was just not paying off and I decided to quit trying to brestfeed directly. I am very proud though that Alexander was fed EBM from a bottle for 7 months, and was over 6 months before he needed to have formula. That was a lot of work, but it was worth it I think. I used a very good double electric pump - an Ameda Lactaline.
If you do use the nipple shields I would be aware that they can interfere with your supply so I would 'empty' after using them and then maybe feed it (there are other methods that don't cause confusion if you are worried) or store in the freezer?
I wish you the best of luck. Alexander's now 11 months old now and all of this heartache with feeding upset me so much but it was just a small part of his life that he won't remember and it seems like something in the past now!
Anna xx