Just a thought Susie,
When I was doing a candida cleanse within 10-15 minutes of taking the first dose I developed a fever and headache that I attributed to die off. After it was gone I felt much better. Maybe the same happened with your little one. A fever just indicates that our bodies are doing what they are supposed to be doing....fighting off and killing harmful "invaders".
I really doubt it was indicative that you did anything wrong.
Trust your mother instinct. You are doing what is right for your baby girl.