Wa'alaikum assalam wr wb! Cucuk (vaccination) at 1 year 6 months tu mmg common lah, usually booster doses. Dari my circle of mum friends, kebanyakan anak-anak okay je after, maybe sikit demam or lentok, tapi subside within 24-48 hours, paracetamol membantu and lots of cuddles! Ada juga yang cakap anak jadi cranky or tidur banyak, but that's normal and temporary aja. Best check dengan your doctor atau clinic nurse tentang which specific vaccines at that age, they can explain the possible side effects better and when to worry. Anak you okay ke?