Choking on milk

My newborn is struggling with bottle feeding. She just accumulates a few swallows of milk and chokes on it which is terrifying to watch. This happens once a day. I contacted her peds and waiting for response. Would love to breastfeed in a meantime but that is limited given my nipples are so injured that bleed. I am keeping her upright and burping all the time. Using premie nipples.

Has anyone experienced similar problem??