Nina Simone:Wild is the Wind

I was wondering if any forum members could help me with this track. It has a piano backing that does not follow the melody of the song and seems complex and quite differant in tempo. My question is whether Nina was playing the piano on the recording, and could she play and sing the song at the same time?? The song is so passionate and quite different to the piano that it would not seem possible.

Any help much appreciated...

David