breast pain but no lymphnode or mass

im experiencing  pain in my left breast but no lymphnode or mass... but its to painful and my nipple everytime i touch it i  feel the pain also...i dont know if there is a co-relation with my backpain..but i experiencing it too..the first time i felt it last july 2008. and from time to time but this month of dec 2008  much more painful .my doctor gave me before an antibiotic and serrapeptase medicine. and also she me told the possible cause is hormonal imbalance.please enlighten me on this... could it possible that it can be cancer even no mas or lymph node? or it is really hormonal imbalance? thank you.

[japdip]

The breasts may become tender or even painful due to the level of hormones in the body. This can be related to the menstrual cycle which is also dependant on hormone production within the body. Pain is rarely associated with breast cancer except for one type (Inflammatory Breast Cancer) but with this the breast is swollen, red and very painful; not the way you describe your problem. If you continue to have this problem or it seems to worsen you might consider seeing a Breast Specialist.     Regards ...