Hi there! Clearly somethings not been right for awhile and it's so easy to find a lump and automatically think cancer, but it honestly could be anything. Your already in a good position so unfortunately it's just abit of a waiting game, for now there's nothing else you can do. As someone with anxiety I found distraction is really helpful, if you need to vent feel free to message X

Also does the lump hurt? 

Hi. I'm so sorry that you're going through this tough time. We all know how hard the waiting is and I know that the 11th probably feels a long way away. Your family history is, understandably, adding to your anxiety, but it's good that your GP isn't worried. It sounds as though they are being cautious, which again is a good thing. 
Try to keep yourself busy during the next week, do something nice with your little boy at the weekend, the distraction will help. Have you confided in family or friends? They will want to support you and it helps to be able to unburden your feelings. 
Will be thinking of you on the 11th, please let me know how you get on. In the meantime, if you need a chat let me know x