Much, much better! Yes, the extra cutting has now caused him to be in considerable pain. His behavior may be more due to that than infection. But it can't hurt to get him on an antibiotic. Give him one half a tablet of the Motrin two times a day.
For the wound, you should continue to soak it each morning in Epsom salts and Betadine or some other antiseptic. This will wash out bacteria that has accumulated overnight and keep ahead of infection. It will also encourage blood flow to the wound which will speed up healing. Keep a thick layer of antibiotic ointment, such as Neosporin, on the wound. Wrap to keep out dirt.
Are you in the US or Europe? How hard is it to get hold of an antibiotic? You may use a leftover prescription for a family member if you happen to have it. Tell us what it is and we'll calculate dosage.