Should I worry

My baby is 17 weeks today ( 3 months) will be 4 months next week. Baby ha rolled from back to belly without assistance a few times but doesn’t do it all the time. If I put baby on side will then roll onto stomach. Baby doesn’t roll from stomach to back at all without assistance. But will grab for toys, and when on tummy time does a swimming motion and can scoot self in different direction. Baby hates to be laid back will lift self up into a sitting position which I believe means baby is getting ready to sit without assistance soon. Also I don’t do walkers as I don’t like to contain baby but should I get one to help baby. I’m an over worried mother ik like some days I get sad if I feel baby and I didn’t play enough or read enough books but my little one seems happy. Laugh all the time smile and love kisses. I just have so many questions at the 4 month appointment 😬