Hello, I am a 20 year old female college student. For the past couple of months I have lost a lot of weight. I am about 5'4" and I went from 125lb to about 117 lb. I have a very rapid heart beat, nausea when I eat, a hard time sleeping, and a cough up a lot of green flem and have a lot of green nasal mucus. What is going on with my body? Please help me.