acceleration or transmission?

i was going down the road passed a car at about 45 miles an hour got over when i did i hit a reflector in the road and my car acted like it didn't want to go like something was holding it back, almost as if the emergency brake was pon can someone plz point me in the right direction as to what might be wrong wrong with it ..no warning lights of any kind on the dash it goes in gear but wont go like it should like something caught in it