Hello, It is not uncommon at your age to have menstrual cycles where an egg is not actually being produced. The periods then come erratically rather than regularly, and can be light or heavy. And sometimes during the perimenopausal time of life, a mature egg can be produced and it is possible to become pregnant then. Nausea and breast tenderness can happen with the erratic rise and fall of hormones during menopause. If you were my patient, I would check the following: complete blood count to make sure you are not getting anemic from excessive blood loss, thyroid tests (TSH and thyroxine) - these are blood tests. I would also do a urine pregnancy test if there is any likelihood for that. A breast exam is appropriate if the tenderness is in only one breast. If you like natural remedies, red raspberry leaf tea can be helpful. Otherwise, your doctor may consider helping regulate your periods hormonally if they are giving you much stress. I hope this helps answer your questions.