My DS did better when I started playing visualization relaxation stories for kids before bed.
When he was in that phase he had so much emotion he couldn't control himself and couldn't calm down.
It's okay to just step away from the toddler for a few minutes to calm down. Even if she doesn't nap, she still should have quiet time either laying with you or playing with a special QUIET time only you. Gives YOU a break. I say "mommy needs quiet time too". Schedule the toddlers quiet time when the baby will be napping.
Do you have any family in the area? A friend that can come over? Preferably who has small children so she can reassure you that you aren't crazy.
WAHM and WOHM of 2 little ones