Meeting My Boyfriend's Mom

so my boyfriend and I have been together for a little over a month. I am half black and half mexican, and he is full Native American. he's already met my parents but I am afraid to meet his mother because his family is very traditional and I'm sure they want him to be with a full Native American girl...I'm scared because I don't want her to meet me and get upset and tell him that he can't see me anymore... I don't know what to do. advice please?