Sharp pain in one side of face, had a tooth removed there, may be infected but no insurance. what is the best way to get checked for infection? thanks

Emergency room: If you have pain, and especially if you have fever, go the emergency department of a nearby hospital. With or without insurance the hospital is obliged to address emergent issues. For follow-up care you may go the dental clinic at the local Dental School. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex. Get HPV vaccine.

Only one way: See a Dentist. Best to see the Dentist that did the extraction who already has baseline data. Infections need immediate treatment.