hi,
sometimes factors like stress can exaggerate symptoms of
premenstrual syndrome,
so your sore breasts could be because of PMS or
pregnancy,
so you better to wait till your expected date and undergo
blood test for pregnancy which will rule out the possibility of pregnancy,
till that you can take analgesics like
paracetamol to relieve pain, if they do not help better to consult your doctor once and get examined.
take care.