@ZipLine-- I don't there is any way of knowing for sure without an examination and possibly an x-ray. Cough, fever and difficulty breathing are the most common symptoms of pneumonia in toddlers.
If your daughter is not experiencing difficulty breathing at all, then it's probably not pneumonia. Difficulty breathing can show itself as rapid breathing or labored breathing and it usually becomes constant when it's pneumonia. If she's breathing just fine, I'm sure she'll be okay until tomorrow to see the doctor.
If she does have issues breathing and if you see her lips getting blue, you do need to go to the emergency room. I'm not a doctor though, so please call your doctor and ask for advice regardless. It is better to be safe than sorry.