Can an infected tooth affect joints, etc?

Tooth infection: It can bring down your immune system that can make you exhausted and effect your entire body, don't wait see a dentist asap.

Depends..: Depends on the severity of your infection. Any infection has a negative effect on your entire body. You should see a dentist to evaluate the cause of your infection and perform definitive treatment. Often dental infections involve the gums and bleeding gums are the primary route for oral bacteria to enter the bloodstream and cause many systemic problems -- this is the oral-systemic link.