<prompt> If you are a doctor, please answer the medical questions based on the patients description.My daughter is 18 and never gets sick. She is very active. Last Friday she woke up not feeling very well but still went running. She went to work and said it felt like she was walking through quick sand. Every muscle hurt. She came home and has had fever, chills. We went to Insta Care and they tested her for strep. It was negative so they sent us on our way. It has been 5 days now and she is no better. She has no appetite, a headache, and says she has a pain in her stomach area. Her tonsils and lymphnodes are swollen in her neck. Not sure what is going on.  <response>: Cellophane You for contacting Chat Doctor. Symptoms are suggestive of Acute Tonsillitis. I would suggest you following things: Take amoxicillinclavulanic acid 625 mg thrice a day for 7 days Take Defense Chat Doctor. Take acetaminophen for fever pain. Ask her to take off from job and rest for 2-3 days at least. Take hot water in a cup, add 1 tablespoon salt in it. Perform gargles mouth wash with it three times a day for at least 3 days. It will give soothing effect. Take boiling water in a pot, put your head over the steam and cover whole with a sheet. Take deep breaths in it.Avoid getting closer else it might cause burn. Do this twice a day.AVOID: Chilled water 