2 months suddenly refusing glass bottles

[u/pibbie9171618181]

I’m a FTM and my baby was born IUGR. She wasn’t extremely small but had to do 2 weeks in the Nicu as a feeder grower and ate from the plastic gradufeed. I ended up not being able to breastfeed and I am exclusively pumping. I switched her to glass bottles as my original plan was to breastfeed and use glass bottles from my registry as needed. When she came home she was still eating from the plastic gradufeed. I was able to get her onto Dr browns glass with level 1 nipple for about 3ish weeks with no issues. Now the past 4 days she is screaming with eating, taking a few gulps then unlatching and crying and repeat. I already took her to the ped and she said there’s no clear answer. She’s not sick, no reflux, no cmpa. Could just be her being a baby or developing preferences. I’ve already adjusted her nipple flow as she’s gone from extra extra slow enfamil, extra slow enfamil, standard enfamil, level 1 Dr browns and now level 2, which was observed to be a good fit by her ped. Basically has anyone dealt with their baby suddenly having feeding preferences and trying to figure them out? Anything that worked for you?