worried sick about breast cancer after referral?

About 7 years ago my right breast began to feel tender,not painful just a dull heavy ache and then 3 years ago my sister who was then 34 was diagnosed with breast cancer, she also had a negative gene test but after she was diagnosed it prompted me to get checked,my GP said i was naturally lumpy probably due to my size (42dd) but said she could not feel anything to worry about but given my sisters history she referred me for a scan which was clear,the achy,heavy feeling never went away but started to become more frequent in me noticing it so today i went back to my gp and this time she said she could feel something on the right side of my right breast but said my underarm felt normal,she said it did not feel like a lump but more like nodules,she also said "there is nothing screaming out at me that it is anything major" but when i asked could it be cancer she said there is always that chance but she didnt think it would be but has once again referred me for a scan i should get the appointment within 2 weeks,the area she felt what she called nodules was a little painful when she was pressing it,when i examined myself i couldnt feel anything at all,she really had to press hard to feel what she felt,i am 34 the same age as my sister when she was diagnosed,cant feel any lumps,no discharge,rash or dimpling or thickness and every time i look at my 4 children i just want to cry ,i am now getting scared about the scan thinking i cant go through with it as i dont want to hear bad news