Just thought I'd add my experience into the mix, Katie, but this is what worked for me, not necessarily something that would work for everyone, or something your HV would recommend!
I used nipple shields with all 3 of mine. I hated the fuss of using them, though, so wanted to wean them off them asap.
With each of them, I picked a day to go 'cold turkey', then spent the day relaxing in bed (good excuse!), with lots of skin-to-skin contact and 'snacking', by which I mean allowing the baby to have the nipple whenever he wants to, and in whatever position feels comfy. I have to say this was not easy for any of them (or me)-they all screamed when the nipple shield wasn't used, and I had to be really harsh, but I was determined to get off them!
I found 'rugby ball' was good if they would take one side and not the other-they'd often take the 'rejected' side if held rugby ball style. Also my ds2 loved to feed lying down, but neither ds1 or ds3 would do it, so they really are all different even at this young age!
I managed to get all 3 of them off the shields at around 3 weeks for each of them, but with each I waited until they had put on plenty of weight, and made sure my supply was good (I think I was expressing as well, so we had extra if we needed it) and I was quite harsh with the cold turkey thing- no going back for any of them once I decided it was d-day!
All 3 of my boys went on to be breast fed until self-weaning, at around 15 months for each of them. And all 3 were fantastic feeders after very difficult starts.
Good luck with whatever you decide to do, Katie. It sounds like you're doing all the right things. Like others have said, enjoy feeding your baby in whatever way you choose. It's the bonding that takes place whilst feeding that's most important, not the method used, imo.