My dentist recently pulled 2 of my teeth, one on the lower right and one on the upper left, which were scheduled to be pulled late last year but had to be rescheduled due to the development of blood clots in both of my lungs. Yesterday, I had to re-visit my dentist due to severe pain in several teeth above the extraction area (one extraction resulted in complications due to excessive blood loss... I'm on blood thinners due to the clots). He suggested another extraction or a root canal and prescribed 500mg of Penicillin for an antibiotic and subsequent pain relief. This evening, swelling and pain have both increased and have moved up into my cheek, just below my right eye. The swelling is noticeable and the area is hard to the touch. Should the Penicillin (taken 4x a day) be kicking in by now or should I consider immediate emergency care?