Please do respond to this

M a first time mummy to an 8 weeks old. En m giving my son breast milk but due to low milk supply m somewhat like 50% formula 50% breastmilk. What m worried about is eversince i've started breastfeeding i have a noticeable difference in my boobs. En I give milk equally through left en right boob. But still right one is quite big as compared to the left one. M so worried please share if anyone has witnesed this in BF period. Do u think its normal?