I Am Underweight And Very Sick
Thanks for posting your query.
You are in a quite young age, you have described your state but not provided any data on what is going on, I am sure you are not happy, The kind of brief communication you have made makes me fear that you might be depressed as well.
Please provide details since when you are sick and what are the main problems that you are having and give their duration.
Did you loose your weight or you never gained it.
Please get a base line evaluation that will give vital clues.
Random blood sugar levels, CBC, RFT, LFT, Thyroid function tests, Chest Xray, ECG, ECHO, Urine examination.
Please put up a follow up query with the details and results of the investigations.
If you have any questions I will be happy to answer.
Wish you a good health.