Spitting up baby

Angel • engaged💍👫 baby in heaven 👼 beautiful baby girl 5/8/2019 🤱👨‍👩‍👧 due July 2020🤰

So I recently switch back to breastfeeding I was only pumping. lately after every feeding she spits up. is this cuz she's eating too much? She never spit up very much when she was bottle fed.