If pregnancy has been ruled out , then these symptoms can be attributed safely to premenstrual syndrome which manifests as sore breasts, headaches, nausea, mood swings, decreased appetite, increased frequency of urine, lower back pain and many such symptoms which mimic early pregnancy. They usually subside once the menstrual flow is established well.
But in your case when the bleeding lasts only for 1 day then you need to be evaluated for hypomenorrhoea in form of hormonal profile for hormonal deficiency, an ultrasound pelvis to look for polycystic ovaries ( to rule out PCOS) . You need to visit your physician for an evaluation and examination soon.
I hope i have answered your query in detail,
wishing you good health,
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.