I have a severe sore throat, fever, congestion, headaches and nausea. i have been taking an antibiotic for a toothache. why am i getting sick if i have been on an antibiotic?

Sore throat: Many sore throat, runny nose and cough are from a viral infection. It just need to run it's course of 7-10 days. Antibiotic will do nothing and can be the cause of upset stomach. Bed rest, hydration and otc cold and cough medicine will help you.

Unrelated: You may have got the flu and it has nothing to do with your tooth and or the antibiotics.

Different infections: Different infections need different antibiotics! unfortunately a single antibiotic may not work for both a toothache and sore throat/congestion. See your md!

Virus vs. Bacterial : Often a "cold" is viral in nature and will not respond to anti-biotics. A tooth ache is typically caused by bacteria so an antibiotic can be used for the infection if deemed necesary. If your cold is viral, antibiotic most liekly will not help.

Antibiotics treat bacterial infections. Your symptoms indicate a viral upper respiratory infection, such as Flu. Did you have a Flu shot? See your General Practitioner or Urgent Care for diagnosis and focused treatment.