I have sudden onset fever. Temp 101 and body aches, chills, but no cough or sore throat? Is this flu?

More info needed. While we can't diagnose this without more information, we can say that fever, body aches and chills are common symptoms of the flu. Since flu is prevalent now, we often begin flu treatment without a positive diagnosis- that is based on the symptoms and history. Antiviral treatment works best when started within 48 hours of symptom onset, so best to call the doctor as soon as flu is suspected.