Thanks for posting your query.
Although your mother is taking pills for raised blood pressure, but there is least chances of getting raised blood pressure after applying heating pad
There may also be chances of tingeing dizziness
due to impacted wax in ears.
You should consult with internal medicine specialist/ ENT surgeon and should go for thorough check up.
Your mother should clear ear wax
and get relief.
At times dizziness may be due to impacted lympholith in inner ear
She should take blood and take medicines under guidance of treating doctor.
Dr. Mayank Bhargava