Do I have a doberman or a miniature pinscher?

I got a little puppy today. the people that gave us the dog said that she is a miniature pinscher but my friend says that shes a doberman. my puppy is 7 weeks and shes really small. She has medium size paws and her ears are floppy. im really scared cuz my mom wants a small dog and won't accept a big dog. pleasee help mee:(