My 8 month old LO is the same. She keeps spitting and pushing her milk bottle out. I think she is also teething so dislike anything in her mouth. What I've tried to do is feed her smaller portions more frequently now (cos she was wasting my precious ebm). On top of that, I let her hold something to distract her (most of the time just the bottle cover). It seems to be working. You can try that out and see :)
It could be because of teething make his gums sore so he refuse to drink or cries when he drink. I believe it is a phase and will go over soon. You can probably ask PD to prescribe teething gel to soothe baby gums . Or is it time to change teat size already?
Elise Low