Thank you for your query Hair loss, irregular periods could occur as a result of hormonal imbalances/ deficiencies . Polycystic ovarian syndrome (PCOS) and Hypothyroidism/Hypethyroidism (thyroid gland malfunction) may be responsible for your symptoms. Autoimmune disorders ( your immunity attacks the normal cells in your body) can cause patchy bald spots. Stress aggravates and triggers auto immune responses. PCOS is characterized by multiple small cysts in your ovaries that fail to develop and ovulate and lead to a hormonal imbalance which results in irregular periods and fertility problems. If however, your periods have been regular and this is the first time your period is delayed, take a Home pregnancy test. If negative even after two weeks of the period s due date, visit your OBGYN. Ovarian cysts (functional are more common) can throw your hormones off balance for a couple of months before they resolve on their own and your periods are regulated. suspicious looking cysts may need to be excised depending on its type and size. I recommend seeing your physician who could refer you to a dermatologist and OBGYN for expert care, if required. in the meantime, try to relax. Notice if you have used any new personal care product or changes in diet and lifestyle that could have triggered the hair loss and delayed your period. Hope this helps. feel free to get back to us if you have further queries. Wish you good health