Just worried.. (cat stuff)

So this is completely unrelated to anything I posted about last time (I don't think this had started then). I don't know why I'm writing about it tonight and not tomorrow when I know more, but I just wanted (not exactly) to.
So I have 2 cats. One is 4 years old and the other is 16, which is getting on in years. Though for cats age is strange.. dogs it varies based on size and breed, and so people tend to expect to be able to predict it better. Cats.. can live 12 or 15 or past 20.. I choose to either believe she falls into the last category or to simply choose to forget how old she is (that works pretty well actually).
Anyway, it fails unfortunately when she gets sick or hurt in any way. Then I remember... and I worry about the younger one if he ever seems ill, but that hasn't really happened much.
Well, I am not home/awake for a lot of hours to interact with them. So I guess the bulk of my interaction is that they sleep with me. But I noticed a couple weeks ago that she was acting weird. She kept going into the bathroom or the kitchen and meowing obnoxiously by the sink.. I guess wanting water. This has happened before. I got out this fountain thing I had, and that stopped it for a couple days. It started again, and I put out another bowl of water.. but she kept knocking every bowl of water I'd put out over or just sticking her paws in it and making a huge mess. I started pretty much ignoring the noise. Finally, after reading stuff online I got worried, and I decided that she really wasn't drinking enough, so I put out a bowl in the kitchen and added some chicken broth to it to encourage her to drink. She drank that, and the meowing mainly stopped.
Next odd thing was on Thursday or Friday, I came home and there was what seemed to be blood on her paws.. like dried. I couldn't find a cut. she wasn't limping. I thought maybe it was dirt? or I didn't know.. then Saturday she came to me with blood by her mouth. That's when I started freaking out. I don't know if anyone has cats, and if you do you probably know how hard it is to open a cat's mouth for more than a second. I couldn't see anything wrong. It seemed to be by her gums. I didn't see a broken/missing tooth. Her tongue looked fine. It wasn't like actively bleeding. It seemed to happen when she ate.. but this was when the vet was closed for the weekend.. so I got to panic for 2 days. I figured out the blood on her paw was from trying to clean her face. I also felt like a terrible mom for not being able to wash the damn blood off.. I tried water.. I bought these like bath wipes because I didn't want to bathe her if she was sick.. finally I bought baby shampoo and tried that.. still not much luck. It looks awful. Pretty sure the vet will judge me for this.
She is still eating some? But I don't think much of the dried food.. I bought canned food but it was a weird consistency that neither cat had much luck chewing (stringy), so that was kinda a failure. Yesterday I bought lactose free yogurt for her (not sure that's vet approved but I knew she likes yogurt and I at least bought the lactose free). She ate that.
I am taking her to the vet tomorrow. I couldn't get in today before work. She's still up and about and still sleeping on the bed. I can tell she's not feeling well, and of course my mind is on worst case scenario because I have no idea what's actually wrong with her. I can only think of what I've done wrong and how I should have taken her to the vet last week. I actually don't take either cat often enough.. they don't go for checkups at all really. Anyway.. yeah. So she's sleeping curled up on a sweatshirt of mine on the floor. I gave her that to make up for washing her paws. I might let her have a tiny bit of ice cream later, and if I do I am probably not telling the vet that... already enough to judge me for I'm sure.