Got Teeth 31 And 32 Extracted Yesterday. Taking 800mg Ibuprofen

Got teeth 31 and 32 extracted yesterday. Taking 800mg ibuprofen for pain, and still taking the antibiotic. It isn't really swollen but there is pain. I have noticed yellow stuff around the extraction area, the stiches, and the tooth in front of the extraction area. Is it already infected? Is the yellow stuff food, if so how do I remove it since it is hurting? Help.