what are "perfect intervals" ie: perfect 3rd or 5ths? are they just normal 3rds and 5ths, or is there more to them?
Seconds, Thirds, Sixths, and sevenths are major or minor. Fourths are perfect or augmented (sharpened) and Fifths are diminished (flat), perfect, or Augmented (sharp).

Sevenths can also be diminished, meaning that it is a whole step below a major seventh.