Hi Chetna @Madhokraj , I’m not one who gets headaches, and I’ve had diabetes for ages. In fact, I’ve not taken more than a handful of “Tylenol” type tablets in my life-time, and those were used following surgeries. As Dorie suggests, these headaches should be brought to the doctor’s attention.
Occasionally, I’ll be awakened by an unusual pain in the lower section at the back of my head and I take this as a signal to check my glucose level - and I find my BGL is always low. For me, any hurt in my head is a signal of on-coming hypoglycemia.
One additional thought - she may need to get her vision checked - headaches could be a sign she needs glasses. In addition diabetes can affect the blood vessels of the eye, so she should have a diabetic eye exam each year or as recommended, so they can track to see if any changes develop over time.