My 11 month old has this rash looking stuff on her arms by her wrist and back of the neck going behind her ears and the front of her neck kind of on her chest it looks like little pin pricks but the er dr said it was eczema and not a petechial rash?

Rashes often relate to transient issues like illness/allergy/contact with agents. A visual exam would make labeling more accurate & since I cannot see it or review any pictures (on this site) you may just need to see your doc to sort it out.

Eczema may be an early sign of allergies. During infancy, food allergies have been associated. If the baby is otherwise well, infection is less likely. Many infants resolve their eczema by age 3 years. A food allergy panel blood test may be useful. A skin plan includes an eczema moisturizer for infants. Avoid irritating the skin. A virtual consult with Healthtap is available.