So update help

I am 12 days late and I've had multiple negative's! I called my doctor Friday and left a message saying I'm late again and the nurse called me back today and said that my doctor wants to do blood work and a pelvic ultrasound but i have to schedule the pelvic ultrasound. And then schedule an appointment to see her about a week later to talk about the results. I told her I'm going to take a test Wednesday she said well do u want me to tell the doctor and I said no but what if it's positive she said well call us and then she probably will still want u to go get blood work and the pelvic ultrasound. I asked if I am pregnant (I would be 7 weeks as of yesterday) would the ultrasound person tell me she said probably not and they aren't trained to look for baby's so they probably won't notice anyways and the information and pictures they take will be sent to someone who can tell what's going on. So I'm excited cause I am actually going to get answers cause last January I was late and all the doctor told me was to tell her if it keeps happening. But it stopped and now it's happening again so to finally get answers and finally figure out what's wrong or if I am pregnant would be amazing! But is there a chance they would put me on birth control? Like what would they do? Or what could they find if I am not pregnant? What would be wrong?