I am sorry to hear Candy is having seizures for the first time.
Since she is 8 years old, this would not be epilepsy. Dogs are born with epilepsy and have seizures start when they are young. When older dogs have seizures, it can be from liver disease, low blood sugar, low thyroid, or brain diseases like meningitis or brain tumors.
They can also have "syncope", which is caused by poor circulation to the brain so the brain is not getting enough oxygen. Syncope is usually due to a heart arrhythmia or heart disease.
Since there are many reasons for an older dog to have seizures, the place to start is a thorough physical exam by a veterinarian, her blood sugar level checked, etc.
If you can't get her to a veterinarian tonight, check her gums when she has a seizure. If her gums look pale during the seizure, this may be syncope, and a heart problem. If her gums stay a normal pink color during a seizure, then it is probably not her heart.
You can also try putting Karo syrup or honey directly onto her gums to see if raising her blood sugar level helps.