my special needs kitty is not feeling Erroll

I have a 16 year old diabetic cat. She had been diabetic for 8 years. Yesterday she wouldn't eat and threw up a lot. Today she ate once, actually meowed for good. She had been drinking the whole time. I know she is getting old. I'm just worried about her. Her little paws are cold. But she is still out and about, walking around, up and down stairs and snuggling us. Any thoughts? Oh and I have reduced get insulin since

I'm sorry but I read your post three times and I have no idea what your question is.
   
Please repost and I will try to help you.

Any thoughts on what may be wrong with her and what I can do to make her feel better?