I feel very bad.
我感觉不太舒服。
Shall I call a doctor for you?
要我帮您叫医生吗？
I'm sorry to hear that you are not feeling well. What's the problem?
听说您不舒服，我很难过，您哪里不舒服？
Have you had any fever or any other symptom such as a sore throat or a cough?
您有发烧或其他如嗓子痛、咳嗽之类的症状吗？