Longhorn,
If you look at the OP's first message...it says that she is half Chinese and half Spanish. Spanish as in meaning her family is from Spain, not Mexico.
Plus, please learn a little bit about the Latino culture and history before you make a comment like "asians look hispanic" because there are more than 20 different countries in Latin America containing influences ranging from their native people all the way to the Europeans, Africans, and Asians. There is a great diversity in the Latino population, with the rising population of Latinos in the United States and you wanting to become a doctor serving US citizens, I think it would be in your best interest to avoid making such generalizations.
OP,
I guess your question was answered already whether you would be considered a URM. But the only thing I have to add is that the reason for URM statuses set by medical schools is in part for two reasons. One, these groups are heavily populated in the US yet not in medicine. Two, these groups have significant health disparities and statistics show that these health disparities are not being addressed as much from people who do not consider themselves from that community (most people go back to serve their own community).
Betacell,
I disagree with the fact that Central and South Americans are not considered URMs but my guess for an explanation would be because they don't have as large of populations in the US as the other groups minus Native Americans. But I'm sure, according to schools, they are considered 'unofficial' URMs.