Had back tooth pulled 2 weeks ago with slight infection. now jaw is locked up. haven't had tetanus shot in over 20 years. is it to late to get one?

TMJ: Your jaw is locked because the disk in the TMJ is displaced. See yoou dentist, as for a referral to a TMJ doc. See a TMJ-orofacial pain expert to help evaluate and treat your problem. A TMJ-oro-facial pain expert can be general dentist, an oral surgeon, prosthodontist, orofacial pain specialist. Ask your physician, dentist or dental society for a recommendation.

Trismus: The most common complication after infected tooth extraction is trismus also called spasm and tightness in the jaw muscles. The best treatment is moist heat and jaw exercises.

Not Tetanus: You most probably don't have Tetanus ("Lockjaw"). see a TMJ specialist to treat the locking problem. No tetanus shot needed.