How to numb the pain of my infected insect bite besides a hot towel and aspirin?

It may need Drainage. You need to see a physician. If you're having that much pain then I would be worried you have an abscess and this needs to be drained and then given antibiotics.
Heat = worse. If it is an acute bite, then cool or cold compresses will relieve it, heat will make it worse. If it's been there a few days, and now it's painful or oozing, see your doctor.