I am 19 years old, female, and I don t have an eating disorder, but I noticed that frequently, when I get up from sleeping, I wake up hungry, my body is shaking from hunger, but when I eat, after a few minutes I end up vomiting everything that I ate. I have low blood pressure and sometimes low glucose level, so I thought maybe that s the reason for having these problems. My friend also said I might have gastritis . So, help?