Baby feeding lesser than in the past

Hi mummies, my baby is currently 4.5 months and has been drinking significantly lesser ever since his 4 months vaccination appointment 2 weeks ago. He used to drink between 180-200ml per feed (5 feeds a day), but is currently only drinking about 120-160ml of breastmilk per feed. We were reading up and his signs seem like it was feeding aversion as he would cry when he sees the bottle and when placed in a feeding position. But this has not happened in the past 1-1.5 weeks, and he would just push the bottle away signifying that he is done with his feed, and we would also not force him to continue. However, since his total daily volume is quite low, we’re still quite concern about this. Are there any mummies out there who’s experiencing the same thing with their baby as well? Thank you. #advicemommies #firsttimemom