Could be pregnant or a bad case of worms...they will swell with worms and sleep because they take their energy away....take her to a vet.
Do you remember her being in heat....rolling, howling, loud purring.
I really wish you would get her spayed...I have 4 stray cats that I am now the proud owner of and have had all of them spayed/neutered. I also have 2 rescued dogs.
Just this morning a young male cat shows up on my door step, needing neutered hair brittle(from lack of proper nutrition, or ill...who knows). From his condiiton if I take him to the shelter he will be put down. They have enough healthy cats to adopt out much less taking time with treating, neutering an ill cat.
I feel the responsibility of doing something for him so I will take him to the vet and do what is right by him. Hopefully I can get him placed in a foster program so that he can be nurtured back to health. I have 6 animals in my house and that is enough....I can't take them all...do you get my point....please for the sake of the cat get her spayed.
My neighbor to the left of me has picked up 7 stray cats....my neighboorhood is full of cats as I am sure a lot of neighbohoods are because people will not be responsible. Sad very sad....don't you be one of those people.
Heres a link to cat care. Good luck
Feline How-To Manual: Pregnancy and Delivery ~ Pawprints and Purrs, Inc.