Help! My cat has a lump on her mammary thats concerning me

Please help me, my cat has an enlarged mammary and it's really concerning me. I've been sitting here crying for the past hour and am crying while I'm posting this. I don't know what it is, shes never been to a vet in her life and she's 14 going on 15. The lump has been there for a few years at least, but its getting a little bigger, my girlfriends mom told me it was probably just old age but now I'm not sure if its mammary cancer or old age. I can't get her to a vet anytime soon so I was wondering if anyone could help me, please help me. I can't stop crying, I love my cat. We recently saved her, she had a blockage and we gave her cranberry juice(dilluted) and nothing but canned cat food until she got better. She's got shiny fur and by all means looks healthy, but that bump concerns me.

Unfortunately she's not spayed
I'll have to talk my mom into taking her to the vet

Stripe had a lump at age 4 and it had Cancer Cells in it. They removed her Breast and it came back a Month later and was removed again. She died at age 11 but it had nothing to do with that. I would go to the Vet.

She definitely needs to go to the vet asap, so discuss that with your mum. If she's not been spayed, her risk of mammary cancer is much higher than if she had been spayed, but that doesn't mean that's what the lumps are. But whatever it is, the sooner you get her to a vet, the better the prognosis.