If your mom's dog is older than 5 or 6 years old, it could be something in
the brain. As I have just answered in
a previous post common causes of seizures in geriatric
dogs include brain tumors, bacterial, fungal, or parasitic infections in the brain, or metabolic causes.
Seizures can also raise body temperature, so a cold rag wipe down could help.
The fact that your mom's dog pants and wheezes could mean lung or heart disease. So heart and lung disease should also be investigated.