Awaiting breast clinic a week today … the anxiety is awful

I found an indentation in my breast Monday morning, gp referred me for the urgent 2 week breast clinic. I have two children (14&12) and the waiting is so so awful I feel sick and tired not sleeping… all I can think about is how will I tell the children it’s cancer? 
I keep trying to tell myself it might be nothing but indentations are worse than lumps right?