Birth weight

Hi mommies! Question lang po, si LO ko po is 3mons na last Feb 06, nung last check up namin 5kls lang sya which is not normal for a 3mon old ☹️ ano pong masusuggest nyo na gawin ko. Exclusive bf po ako. Should I mixed feed na po ba? Thank you po in advance. #firsttimemom #advicepls #firstbaby #pleasehelp #FTM