Nursing strike....help!

My baby all of a sudden doesn't want to nurse. She screams her head off and if she does latch, she's all restless and kicking off of me or yanking her head back like she's frustrated. I know there's milk because when I squeeze my nipple, it shoots out everywhere. 
She does get bottles of expressed breastmilk regularly. I give it to her with the slowest flow nipple that shes been using since birth. She's currently 3 months old and nothing has changed as far as her bottle, nipple, amount of time between feeds, etc. 
I need help 😞 How do I fix this? I still want her to be able to nurse because there's times I'm out all day and can't pump.