I don't know what to do...

My son had a physical today , he weights 23.12 & he's 29 inches tall.

His pediatrician said he should weight less. He's 7 months & i'm EBF + solids. He wakes up every 3 hours to eat at night , She says i should try stretching his sleep to 6 hours without eating. 🙄 Idk what to do, i dont want to starve him. Any advice?