I don't think the notion that is HAS to hurt is right, although it often does... the key is getting the right advice from people who are real BF experts, and unfortunately sometimes this is not midwives, though some are. I'm not sure why you needed to give top ups for example (unless there was some other clinical issue, since your baby was putting on weight) and I'm not convinced therefore that your MW is giving the best info. You'll get very up to date advice from the National Childbirth Trust helpline, the Breastfeeding Network helpline or the La Leche League helpline and all their websites are excellent if you or someone else have time. Also www.drjacknewman.com has good latching advice including videos so you can see what to try...)
The lansinoh helps a lot, and there's lots of other things you can try but the key is getting help with your positioning and latch, ideally face to face, from someone who really knows what they're talking about.
Please don't make any final decisions to give up at night when you're tired and it's hard and you haven't been able to get a BF expert to advise you yet... Even if you do have to give the odd formula bottle, you can still carry on and will be better to keep expressing to keep the supply going.
The shape of your nipple after feeds is helpful info and you can describe this to a BF counsellor over the phone and they'll probably be able to tell you how to move your baby a fraction which might help - please keep going...
I speak from bitter experience - all of my early BF experiences were really difficult and I only wish I wasn't so proud and had asked for expert help earlier. But BF is a skill that needs practice and sometimes to be taught - you and your baby are both new to it so it will take you both time and effort to get going...
...and when you do it will be really great for you both!