Breast size can be increased by estrogen or progesterone pills. However, it is not safe to use estrogen in this way because when breast cells are stimulated to grow, they are more likely to turn cancerous. Honestly speaking, there are no published double-blind, placebo-controlled studies of any breast enhancement products at the time. Breast augmentation is the only reliable method that is available. In this a breast implant which is a prosthesis is used to enlarge the size of the breasts. Please consult a plastic surgeon for that.
Regarding the irregularity in menstrual cycles, high level of stress, cholesterol, hormonal imbalance, chain smoking, dramatic changes in your life style and medical conditions like PCOS and uterine growths may be some of the common causes of you irregular periods. I would suggest you to consult a gynecologist and get hormonal assay and ultrasound uterus done to confirm the diagnosis.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your dermatologist. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.