My baby is 3 months old and has never had a spit up problem. She's been on the same formula for…

My baby is 3 months old and has never had a spit up problem. She's been on the same formula for quite some time and has never had any issues with it, but just over the weekend, she has started to spit up after almost every feeding and seems like she doesn't feel good. Is it normal for babies to develop reflux? I'm so lost 😞. Considering calling her pediatrician in the morning but idk if this is something that's normal or not...