Pain in the left breast

Hello Doctor :)

I am 26 years old , never pregnant/ feeding and I had long term pain of my breast but only of left one , never of the right side.
I have been going to see doctor regarding this since few years.
In the beginning the pain was close to the middle of chest and under the breast. I could feel painful area about square inch area , very sensitive skin in this area as well, pain lasting all the time.  I have been told it might be related to hormones, muscles underneath the breast tissue or heart.  I had my hormones and the heart checked few times and it was all good. I would like to add I have very systematic periods and of course before menstruation I feel equal heaviness of both breasts. It has been over 3 years as I have this under breast pain, and recently I have another - additional pain also of the left breast but located on the upper outside part, close to the armpit. It hurts when I touch and itself . The pain is more intensive after exercising.

Is it possible that muscles and tissues in breast are wrapped around in the weird way so they cause pain?
Is it possible to have a pain that is related to hormones all month long, lasting forever and only of the left breast?
(If it is possible is it common?)
If there is something to worry about or check what kind of exam should I get?

I would like to also add I had just done blood tests done and it showed :
a little low MPV & Magnesium,
and just little bit higher OB and PDW ,
the rest quite good.

Thank you ,

Best Regards!
P.
http://www.medhelp.org/posts/new_with_new_subject?forum_id=121#

[Cleveland Clinic]

Dear Paulinka:  As this is a breast cancer forum, our expertise is not breast pain.  Breast pain is quite common and not generally related to cancer.  We recommend that you seek the advice of a medical breast specialist (usually affiliated with large academic medical centers).