Chest fullness and pain, delayed menstruation - what's the reason?

Patient's question:

Chest discomfort, menstrual period delayed for 6 days and still not coming, I used a pregnancy test and it was negative. What could be the reason? Please help the expert explain this, thank you

Doctor's answer:

Guidance: It is normal to experience breast tenderness and pain in the early stage. Patients often experience breast or nipple tenderness, sometimes even to the extent that they cannot touch their clothes, and it feels like there are hard lumps when pressed. Don't worry, it will return to normal after menstruation. If not, it is recommended that you switch to low-fat dairy products. Bran helps to boost energy. Consuming whole grains, fruits, and vegetables can increase your fiber intake. Try to avoid alcohol and reduce your sodium intake. Eating more celery can help with diuresis. Vitamin E can alleviate symptoms of fibrocystic disease, while vitamin A can reduce pain.
Doctor's inquiry: