Is it normal to be just sore??

My right boob is tender to touch and nipple hurts I think she changed her latch today or something but I woke up and neck it’s just really sore to touch, I put heat while she nursed in it and I think it helped empty it ALOT I still pumped an oz out after she ate it’s completely “flat” w no bumps or weird colors so I’m assuming my tissue is just sore but not sure if that’s a thing