Broadly speaking, a dog that is not eating may not feel well due to disease within or directly affecting the gastrointestinal tract, or as a side effect of disease elsewhere in the body. For example, Star could have eaten something that is upsetting her stomach and making her not feel well, or Star could have something like advanced kidney disease that is making her nauseous. These are just two examples of many things that could be going on, but my point is that it can be challenging since dogs can't just tell us what hurts or what's wrong.
Given that she's on m-eloxyn (I assume this is a brand name of meloxicam), this makes me concerned for gastrointestinal ulceration. Just like if a human takes too much Aleve or Advil, we can get stomach ulcers, dogs can be very sensitive to this type of drug (meloxicam is an NSAID, or non-steroidal anti-inflammatory drug).
Because her anorexia has lasted more than 24 hours, my best recommendation is that she be evaluated by her primary care veterinarian. They will examine her, assess hydration levels, abdominal comfort, heart rate and respirations, among other things. After her exam they will make recommendations for diagnostics such as blood work (to check liver and kidney function as well as to screen for systemic infection), and imaging (such as x-rays or ultrasound to evaluate her internal organs).
Does Star have a primary care veterinarian that she can go see today?