My left side gets really sore

Okay so I don't really notice pain until I touch it or I see the wound I really don't know why. I rubbed my right side and after that it's like I noticed it's sore as ever can be im 17 weeks and a day did my baby do that? Cause I feel him/her moving around switching positions cause my stomach will get tight and I'll see it but then she/he wil move back I guess? And my chubby pregnant stomach comes back lol but idk I didn't think the baby could reach up by my side kind of my ribs? I babbled I'm sorry lol is it the baby?