7 months old low weight

My 7.5 mo bbg is only 6.3kg. She has dropped from previous 10th percentile to 3rd. She hates drinking milk and will only finish 70-90ml at once and i will have to spilt her 120-150ml milk into two feeds. She is not really a big fan of solids too. On average she is only drinking 400-600ml per day with one solid meal. Is this normal? She is very active crawling and standing now so she is reaching her milestones just fine just her weight always worries me. #firsttimemom