Hey Wendy,
I think they are probably hungry as they are not getting much protein (milk aside LOL) or any more age-appropriate foods. As for how you should treat them - i would go by their abilities. They can sit up in their highchairs right?? Maybe start some finger foods? I know you are scared by them
but they will never learn if they don't get to try it! I started Red with breadsticks, steamed carrot sticks, pasta pieces, fruits, toast, cheese. Give them these along with their puree. Are you doing meat/ fish yet? Are you intending to? If you are then maybe you could add some chicken to their puree??
With Red we do:
Milk
breakfast (cereal and toast and fruit)
snack (only if wingy - fruit, rice crackers, milk)
Lunch
snack (as other snack!!)
dinner
Milk
HTH x x