Breast cancer is a serious medical problem that does require relatively rapid workup and diagnosis, so that proper treatment can be started if you do in fact turn out to have breast cancer. At the same time, however, you should never feel like you are being pressured into something or that you are not having all of your questions answered. Therefore, if you feel like you need more information, you should communicate this to your doctor
who will I am sure be happy to answer your questions.
Generally evaluating a breast lump that is concerning for possible cancer follows a standard series of steps. This may include a mammogram or an ultrasound
or a breast MRI to better look at the breast lump. If, after ultrasound or mammogram there is still concern, usually a biopsy
of the lump is necessary to make sure this is not cancer.
This is a pretty standard set of steps, and if there is a lump present, I think it is very unlikely that another doctor would not have the same set of recommendations for you. Therefore, I recommend that you get your questions answered but also prepare for some addition imaging studies and possible biopsy.