It could be fetal movements! I had the same feelings initially and thought it was gas. But you will slowly get used to it and will be able to tell the difference. I first felt my baby flutters around week 16-17 as well. Don’t worry it will get more and more prominent along the way. Am 25 weeks now and my baby is super active and kicks all the time. :)
Can i ask if it feels like feather or ticklish at the side or the top of your belly? Im 15 weeks and i sometimes feel it.. so idk if its really movements or just my sense of my clothes rubbing against my tummy hahaha