How do I get help, I am a single mother and the doctor just told me I have Superior mesenteric artery syndrome?

I thought I had appendicitis but the doctor said it was Superior mesenteric artery syndrome. I am not 100% sure they are right, they did not do the proper tests but this is what they are telling me and this symptom has a mortality rating of 1 in 3... so what do I do, I live in Arlington Texas and dont have health care.