Is my 4 yr old cat about to die?

I have 4 yr old seal point (siamese) cat. He is an indoor cat that got outside a couple of weeks ago. He got fleas really bad and subsequently, worms. I have given him flea baths, treatments and dewormer. I even treated the house. He still has fleas and worms. I have noticed in the past few days that he is losing patches of fur all over his body and his tongue is starting to turn blue-black in the center. We can't afford a vet. All our money goes to my son's doctors' bills. I don't know what to do! Please help!