A.J.
Relax. I know how scary febrille seizures can be as my youngest had several last year with the flu, but they are harmless. Most commonly they are caused by a sudden spike in body temperatures. Mush less frequently they can be caused by serious issues.
There really is no need to see a neurologist. Have the pediatrician take a look him first before getting carried away. In the meantime, keep hydrating him well with clear liquids as this helps loosen the mucus. And know that coughs can last for 2 - 3 weeks after virus seems to be gone. HTH and good luck. Seeing your baby sick is one of the toughest things about parenting.