Possible uterine problem?

Patient: Hi. I had an ultrasoundin march to look for a possible pregnancy which was not found. The tech asked me if I had had a previous c-section with my First child. I had a vaginal birth. At the time I didn’t think to ask her why she had asked me that. I am wondering if she may have seen something ? The doctor Dudnt tell me anything other than I was not pregnant. I am very worried something may have been seen on my uterus.