She turned me on my head to me, this says, 'She turned me upside down.' (She had such an impact on me (love, shock, surprise) that I felt completely disoriented.)/ Perhaps related to the expression 'head over heels in love'
She turned my head: this has two meanings: 1. she caused me to have an undeservedly high opinion of myself, or 2. She caused me to stop and gaze after her (usually because she was so beautiful).