You should RECORD only on the track for your voice. On your voice track, click the Fx button on the track control at left. Make sure no effects (such as Echo or Reverb) are selected. If any are, delete them.
The music track should NOT be set to record. But if you have already done so, then it might mean that your music tracks now also includes your voice. And that could account for the apparent echo when BOTH tracks are played back; one track is slightly out of timing with the other.
Hope that helps.