Yes it can just happen. There are congenital shunts (from birth) and they can get acquired shunts which just grow at anytime. Or it could be MVD
MVD. The only way to tell is to have the bloodwork done. Both diseases can be managed with medications and special diets, a low protein diet. Some shunts can be surgically fixed by placement of a band around the shunt that gradually closes it off in 3-6 weeks. Then the pup is monitored with bloodwork 3-4 times a year. Just do one step at a time. Some shunts are bigger or smaller, inside the liver or outside and it all depends on how the dog is handling it. Once the Bile Acids Test is done, if the result shows decreased liver function, you may have a choice of surgery or medication. Further testing would be neccessary to determine if the shunt is operable or not. If you choose no further testing and want to try the medication route to see how she does, that would be acceptable. Dogs can live a long, normal life with this disease, on the meds.
Then, again, it could be a seizure disorder, or she may have aspirated some vomit when she threw up, causing a lack of oxygen. Medications can affect liver test values. it's impossible to say without the bloodwork. What they saw was what state her liver was in at that exact moment in time when the blood was drawn. The Bile Acids test gives more information, and if it were my dog,I would at the least have the BA test done to rule out liver problems. First they drawn a blood sample after a 8-12 hour fast. Then they feed the dog a fatty, high protein meal. Then 2 hours later, they draw another sample. They compare these results with normal values to determine if the liver is functioning properly or not. With a liver shunt, some blood bypasses the liver and goes directly to the heart or the brain. That can cause neurological problems, clumsiness as you had mentioned, and or seizures.
Why did the dog have a high temperature? Something going on in her tummy? That can also cause seizures on it's own. So you still don't know any more then when we started. My apologies. This is a tricky disease to diagnose on behavior alone. Could she have eaten anything toxic?