What Causes Pain In Left Breast?

I am 40 and from last three year s having pain in left breast last mammographf done in feb 2013 there were 3- 4 small lump found after some medication they were dissolved but in feb 2014 i found much pain in left breast after doctors consult mammographf was done it shiwed small lump near nipple but i take evion and after some time no pain but from last two three months i feel very uneasy and some pain in the same breast doctor advise me to take simrose 1000 and evion600 should i go for mammographf again or taking these medicine is ok?