Hello everyone, I don't really know why I'm posting on here but I feel helpless. My mum had breast cancer 16 years ago, had a mastectomy and lymph nodes in her arm removed and radiotherapy. She has been clear ever since and has not had any problem. 
On Tuesday last week, she discovered quite a large lump (about the size of an egg) under her armpit on the opposite side to her mastectomy side. The lump isn't hard and seems to be moveable. Of course, this brought back horrible memories. She went to the doctor straight away and has been referred to the breast clinic this coming Thursday. 
this morning my mum has woken up with a pain in her back that she says makes her feel a little sick (though it hasn't affected her appetite and she has eaten breakfast as normal this morning). 
We feel as if we are in limbo at the moment and I can't help but research possible explanations as to what this lump could be. I was just wondering if anyone has had a similar experience and what my mum should expect at the breast clinic on Thursday. I hope we will have answers that day as the waiting is unbearable. Many thanks for reading.