There is really no way around this.
If your turtle is sick, and you have no experience with sick animals, take your animal to a veterinarian for evaluation. The vet will tell you what your options are, and then you can decide what you can afford. Lab work, medications, and doctor’s visits are not cheap, but most veterinarians will work with you to find a solution that helps your animal without you going broke..
To find a veterinarian:
If you don't go to the vet, things will just get worse, and that means your animal will suffer more, and treatment will only get more expensive.
You can wait-and-see if:
- A new turtle is not eating yet, but is active and alert.
- Action: Allow the animal to settle in. Make sure setup is correct. Offer a variety of foods, including live worms and snails.
- Animal has minor injury, such as a small cut or bite.
- Action: Clean injury with antiseptic. Keep turtle dry for a few day except for twice daily soakings.
Waiting is a bad idea if the turtle is or has:
- lethargic.
- kept indoors and stops eating for more than a few days.
- yawning or gaping for breath all the time.
- swollen eyes, bubbles around mouth or nose, and is less active.
- significant physical injury to the body or to the shell.
- losing scutes from the shell, exposing bone.
- And: Something is wrong and you don’t know what it is, but your gut feeling is that it’s not good.