need advice with my newborn!

I have a week old baby. I breastfeed her, which has gotten a lot easier for the both of us. She burps after she eats.. But a little while later she spits up! Is that normal? My mom says she shouldn't spit up breastfeeding! She has a doctors appointment next week, and I'll find out.. But inward wondering if there was anything I can do to prevent the spit up.. And is it okay that she is spitting up breast milk? Thanks in advance!