This is a 1977 Latin disco pop cover version of the blues song originally written for Nina Simone and recorded in 1964 (see: Don't Let Me Be Misunderstood);
there's also a popular rock cover (1965) by The Animals (see: Don't Let Me Be Misunderstood).
Baby, do you understand me now?
Sometimes I feel a little mad
But don't you know that no one alive can always be an angel
When things go wrong, or seem to be bad