My poor cat

You are on the right track in treating your cat.  It's a very good thing that the abscess exploded, even though it was messy.  A lot of the pus (poison) was released, and you were also right to clean out as much stuff as you could.

Clean the abscess with peroxide 2-3 times a day, and follow it with an application of Neosporin or other antibiotic ointment.  Keep going with moist packs 2-4 times a day and make them warm (not hot).  Keep them on for 5-10 minutes at a time, if the cat will tolerate it.

Continue to keep cleaning out whatever matter is in the abscess... the moist packs and Neosporin will keep it from scabbing and allow it to continue draining until it heals from the inside out.  Your cat should be fine.

Good luck... I'd like to know how it goes.

You don't want it to scab over. Just get some antibiotic ointment.  You need to be careful, because you don't know what scratched or bit your cat.  Make sure that your cat is behaving normally, because if he was bitten by a rabid animal, there isn't much you can do.  I know you have no money, but getting a rabies booster vaccine would be a really smart move.