I've been having pain in my armpit area, it has spread to my left breast, I've had a fullness, almost warm feeling in my breast with a dull ache for roughly five weeks now, so far I have found no lump. I have been to my GP this evening who has advised that it maybe Mastitis? I've not breast fed my children for years? I have been given a course of antibiotics for 7 days and told to return for a follow up appointment which may result in being referred to the breast clinic. Could this be mastitis? TIA