How do you know if its progressing?

I was one of those women with no pain, no feeling of being unwell, no inkling at all that the cancer had come back. I thankfully still feel really well halfway through my second cycle of Xeloda for a secondary to my lymph nodes and a spot at the base of my neck C7. I guess we just have to make certain to get checked if there is anything that doesn't feel right or persists longer than it should, for me I was just lucky that my yearly scans in late March picked up the change in my nodes. My check in January was all clear so this re diagnosis came as a massive shock! If you feel well and strong hold onto that and try not to factor in what ifs because they're what do our heads in. I get rescanned in about 5 weeks and am already anxious about it but in reality I can't change the outcome, just have to trust that my treatment is controlling the spread of this hideous disease.