My cat wont eat and wont go to the toilet?

my cat is very old he is about 19 years old for the last 3 days he wont eat anything and is sleeping all the time he wont go to the toilet he just sits in it or last night he curled up and went to sleep in it today he started weesing allot he keeps trying to be sick but noghing comes up. my mum doesnt wont to tack him to the vet because she cont afored it and also hes very old he also is losing wait