We had this the other night (4 week old) from around 5pm until 11pm. Very frustrating and painful, would fall asleep almost instantly but then cry and root when removed. I had hubby try to rock him etc but no joy! Just put it down to one of those days x
Has baby been checked for tongue tie by a qualified professional? (Not just a midwife). Feeding for hours can be really normal my baby often did at that age.. but you shouldn’t be experiencing pain. Is the pain during feeds or only between them? Have you had your latch checked? Sometimes minor adjustments can make a huge difference to the amount of milk transferred x
Have you got any bottles at all? You could try expressing into a bottle and feeding that so you know theyve gotten a certain amount or you could express some and try spoon feeding. You would also pop a finger into his mouth and see if you can feel his tongue coming forward over his bottom gum and making a wave motion. Definitely contact health visitor and get a lactation consult, even if they tell you it's normal and you're doing it all right it will help your confidence
I have no experience, we currently pump due to tongue tie and hoping to get back to breastfeeding… but, could your partner try settle him away from you for a little? Could he be seeking comfort but due to smelling your milk that’s the only way he’ll accept comfort from you?