During asexual reproduction the posterior part of the animal simply breaks off. This is the most common means of reproduction in Dugesia. Regeneration.-- This has been widely studied in this group of animals. There is a polarity that exists in each cut piece.
Yeast Infections are usually signified by itching and burning in the vagina and around the vulva. A white vaginal discharge that may look like cottage cheese and may be odorless or have a yeasty smell (like bread or beer).
Candida (or yeast) is usually not very smelly. Bacterial infections often are. The itching can be caused by either. Cottage cheese like discharge certainly sounds like Candida so you may have more than one organism giving you problems. This one is probably best cleared up by a professional.