Hi Joseph,
I agree with nholmes, that the symptoms you describe may be related to a developing thyroid problem, and that should be tested for as routine, with an older cat (your vet will know--the test is called T4 and is usually done every six months with routine bloodwork for older cats). The change in coat and lack of grooming are of concern. Usually, these are signs that something is happening inside the body which should be evaluated.
However, I also know that sometimes older cats may become disoriented (sort of like senility in humans), as you mentioned, and they cry out because they feel insecure due to this feeling of confusion, and need reassurance.
Older cats can also become very vocal if their hearing is beginning to fail. They tend to cry out a lot to 'test' their own hearing and hear their own voice, which may now sound different to them. You can test your cat's hearing by standing a few few behind her and clapping your hands sharply, once; see if she turns around. Do this only when you're sure she's not sleeping; you wouldn't want to shock her little heart! : ) If you see no reaction, move closer to her and clap again. Don't let her sense you behind her though, or she'll turn around due to that.
If you find that her hearing seems decreased, you can discuss this with your vet and have him check her ears and/or test her hearing at the next office visit.
I'm glad that you found these 2 lumps and she had surgery to have them removed! She sounds like she's doing well, except for the crying, of course. I had a cat many years ago who also had a cancerous mammary tumor removed at the age of 12, and she did very well for several years thereafter!
It was a smart thing to start her on antibiotics, since you and your vet thought there might be a urinary infection, but testing the urine would be the best indicator of an infection or 'crystals' which are tiny particles that can irritate the lining of the bladder and urethra.
If you notice this crying out right after urination (in addition to other times), she just may be 'announcing' what she did, and wants your approval. My cat does this very often when he comes out of the litterbox (he's 13), if I'm not in the same area of the house as he is. It's usually his indication that he wants attention and loving.
I hope your girl remains healthy and you're able to determine the cause of the vocalizing!
Cher
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