Hello. I Have Dropped 15lbs In The Last Three Weeks.

Hello. I have dropped 15lbs in the last three weeks. I'm experiencing nausea, vomiting, loss of appetite, bruising, abdominal pain and bloating, back pain, muscle tenderness, constant headache and occasional numbness of the limbs, abdomen, and lips and shortness of breath. I'm a 23 year old female.