I am 18 weeks pregnant. My lower side breast pain on both. Is it normal?

Hi dear. Most likely the pain and soreness is caused by pressure from the top of your growing uterus, as well as baby kicking or punching the area. Sore ribs are usually on the side of the baby's position and can be felt just below the breasts.

it's normal, you can let your gynae know of you have concerns

yes normal