CHECK ENGINE light started blinking

I'm the original owner of a 1996 Mustang GT 4.6L and...., while driving on the freeway/highway, I stepped on the gas pedal in order to pass the vehicle in front of me but during the acceleration process the CHECK ENGINE ligth started blinking for about 10 seconds then when back to normal I checked engine oil and transmision fluid and everything is fine, on the normal range mark. Engine is running good and strong and the same goes for the transmision. I'm wondering what's going on??
This is the first and ONLY time it happened since I own the car. There is no more blinking light since then, now everything look normal. Will appreciate your response and thank you very much in advance.