Helpppp! Severe weight gain

Hi moms, i’m 31 weeks, hitting 8 months next week. But since my last gynae check at 28 weeks, I’ve put on 4kg already. Gynae told me to keep it within 2kg, anything above is way too much. I’m only eating 2 small meals (like bread/cereal w milk) and 2 main meals. 😨😰😰 how #firsttimemom #pleasehelp Don’t understand why I’m putting on so much weight so quickly