Hi I have an 8 week old. Until now has fed ok though very slow (45min to an hour for 4oz) and has colic. Very sleepy during last ounce
Last couple days he has cried constantly through every feed. Pushes bottle out after couple if gulps. Sometimes seems to gulp too much in, other times struggling to get any out and so tired after first ounce.
We tried going up a level with teat but still though he is getting milk out cries and looks so sad through it
Can't see any signs if thrush in his mouth. Fine between feeds, playful and sleeps ok
It's awful feeding him as he just seems so unhappy and struggling

Going to take him to GP to check if it's a tongue tie but shouldn't health visitor have picked that up by now?
Any ideas what it could be?