How do I know when I should take my dog to the vet?

Certainly, here is a comprehensive response combining all the information:

If your dog feels hot, there could be several reasons for this, ranging from a normal response to environmental conditions to indications of potential health issues.

1. A fever can cause your dog to feel hot all over. Symptoms of a fever in dogs may also include lethargy, vomiting, shivering, red eyes, coughing, and changes in behavior or mood.

2. The warmth could also be due to environmental conditions such as hot weather or physical exertion.

3. Stress or excitement can also make your dog feel warmer than usual.

However, a dog's normal body temperature ranges from 99.5°F to 102.5°F (37.5°C to 39.2°C). If your dog's temperature exceeds this range, it's advisable to consult with a veterinarian.

Apart from body heat, there are several other signs of potential health issues in dogs:

1. **Changes in Appetite or Thirst:** Both increased and decreased appetite or thirst can be a sign of illness. Sudden weight loss or gain can also be cause for concern.

2. **Urinary or Defecation Issues:** If your dog is urinating or defecating more or less frequently than usual, or if there's blood in the urine or stool, it could be a sign of urinary tract disease or digestive problems.

3. **Lethargy or Anorexia:** If your dog seems unusually tired, uninterested in normal activities, or refuses to eat for more than 24 hours, this could indicate illness.

4. **Changes in Behavior:** Significant changes in your dog's behavior, such as increased aggression, excessive panting, restlessness, or unusual anxiety, can be signs of illness or discomfort.

5. **Pain:** Signs of discomfort or pain, such as limping, difficulty sitting or lying down, wincing when touched, or excessive licking or chewing at a particular area, warrant a vet consultation.

6. **Skin, Ear, or Eye Disease:** Symptoms like redness, inflammation, sores, hair loss, frequent scratching, head shaking, balance problems, discomfort when certain areas are touched, redness, swelling, discharge, or cloudiness in eyes require immediate veterinary attention.

7. **Vomiting or Diarrhea:** Frequent vomiting or diarrhea, especially if it contains blood, could indicate serious issues and warrants a visit to the vet.

While feeling warm doesn't always mean that your dog has a health issue, it's important to monitor their condition and note any accompanying symptoms. If your dog seems uncomfortable, is behaving abnormally, or if you're uncertain, it's always best to consult with a veterinarian. They can provide guidance based on a thorough physical examination and any necessary tests.