Please go to the Pediatrician and rule out meningitis,encephalitis and epilepsy ASAP.
And do not panic, Febrile Seizures are very common at this age. It looks scary but it is not that dangerous most of the time, however it is very important to rule out the other causes.
In order to prevent another episode give your baby panadol after every six hours when Febrile. Make sure if Febrile to uncover your baby and in case of low grade fever give him bath. And if temperature rises to 102 f then remove all the clothes and do sponging.