After surgery

I got my surgery(Mastectomy) done a week ago after my neoadjuvant chemo with AC+Taxol. The pathology report says a 4.5cm DCIS left in the breast (original was 4.8cmX3cm solid tumor) and 4 positive lymph nodes with micromatastisis, the biggest being 1mm. The breast has angiolymphatic invasion. I am not sure whether the response was good for the initial chemo. Now my oncologist wants to give 4cycles of xeloda and a year of herceptin. I am kind of satisfied with his treatment plan except the scans. So far I had only abdominal ultra sound, checst xray and bone scan when I statred the diagnosis which makes me scared.They don't want to do any more scans now. Now I am thinking whether it is wise to change the oncologist just for the scans. Aprreciate any inputs.
I am 37 and diagnosed when I was pregnent with my second child.

thanks