Some fibers from the ventral cochlear nucleus cross the midline in the trapezoid body. Thus, cells in the superior olive receive inputs from both ears and are the first place in the central auditory system where binaural processing (stereo hearing) is possible. The output of the superior olive travels in the lateral lemniscus.
Delay caused by a short stress time is usually a week or two, then you ovulate normally. However, under continued stress (heavy exercise, malnutrition, etc.) you can be anovulatory for a very long time. If you are having problems in this area, have a look at this book: Fertility, Cycles & Nutrition 4th Edition.
The menstrual cycle length might vary from 21 to 35 days and still be considered normal. Since your normal menstrual cycle length is 30 days, you are still within the normal range with 3 days late. The reason for being late (longer menstrual cycle length) might be a slight hormonal imbalance. Variations like this might happen in completely healthy women. Sometimes the period can even be completely skipped.