My Bub had a dummy the second day she was born. She's a comfort sucker too. And with your sore nipples try get down to the chemist and get some MooGoo udder balm. It saved my nipples when i breast feeding. You put it on after every feed and you don't have to wash it off before their next feed :)
My bub would feed for nearly 2 hours! He had such a strong sucking reflex, We ended up using a dummy. The first 6 weeks can be pretty tough love, you do what is best for you and your baby. x ☺
My 5 have all had dummies from both and have breast fed fine believe me she will let you k ow when she's had enough of sucking on a dummy that isn't boob 😊 hope it's going well she is adorable