pain in nipple and breast,worried about cancer as it runs in family?

i am 32 and for the past month my right nipple has become very tender and painful,it is not extremely painful just there and noticeable,certain things make it worse like laying on my tummy or cuddling my daughter so its worse when things are pressed against me,i have also had the same feeling but not as bad to the right side of the same breast.the breast and nipple look normal,no changes or lumps,no redness or itchiness or discharge..my sister was 34 when she was diagnosed with stage 3 breast cancer a couple of years ago so i am worried that it could be cancer,i did see my doctor who said to come back in a couple of weeks as my period was due and it all could be connected to my period so i have another appointment next week so any advice or opinions would be great.many thanks..i live in the UK,not pregnant and am 32 and otherwise healthy,i also know that breast cancer does not usually cause pain but pain can sometimes although rarely be a sign