HELP PLEASE!!

Hi everyone, my little girl is currently 6 weeks old and I’ve been exclusively breastfeeding since birth, but I’ve been having issues for the past week and a half.

My baby will show hunger cues (sticking out tongue, sucking on hand, rooting) and I will offer her the breast, but she keeps pulling off, crying and pulling back on/being fussy at breast. I’ll try this for half an hour or forty-five minutes, she’ll also sometimes fall asleep at the breast. At which point I’ll stop breastfeeding, but after a couple of minutes she’ll get extremely fussy.

She kept crying since my last feeding and would only calm down momentarily, so an hour after her feeding we tried giving her a bottled of breast milk I had expressed earlier today and she drank it all within 10 minutes, as soon as the bottle was done, she got fussy again. I tried giving her the breast and she fell asleep almost right away, but when I’d take the nipple out of her mouth she’d wake up and start crying again.

During those times I’ve also tried the pacifier, which rarely works as she just ends up spitting it out. She’s been sleeping less than an hour at a time during the day and keeps waking up crying.

Does anyone know what this could be? Do I not have enough milk? Do I have a fast let down? Is it reflux? Is it just a growth spurt?

Any help would be appreciated as I am really stressed out about this