I HAD A TRAUMATIC BRAIN INJURY DUE TO A CAR

I HAD A TRAUMATIC BRAIN INJURY DUE TO A CAR ACCIDENT IN 1983 SUFFERING IN A SUBDURAL HEMATOMA. I HAVE HAD HEADACHES ABOUT ONCE A YEAR SINCE THEN. I AM NOW UNDER A NEUROLOGIST CARE AND HE'S PRESCRIBED ME LYRICA, FLEXERIL AND LORTAB WITH LITTLE TO NO HELP. USUALLY THESE HEADACHES DON'T LAST FOR MORE THAN 48 TO 72 HOURS AND THEN GO AWAY. THIS TIME THEY AREN'T. HE IS ORDERING AN MRI. MY QUESTION IS WHAT COULD REOCCUR THIS MANY YEARS AFTER?