Welcome to HealthcareMagic Public Forum
Acidity is uncommon to cause headache. Following problem need to be rule out first:
-High blood pressure: As you are already on treatment, so it is better to monitor your BP.
and stress: increases acidity, blood pressure and cause headache.
-Infection of tooth, nasal sinus
So, it is better to get evaluated for above problems.
I hope this information has been both informative and helpful for you.
Wish you Good Health.
Dr. Ashish Mittal