Q: Why does the upper limit of my BP remain normal while the lower limit goes upto 100?

A:You have an elevated diastolic BP. The diastolic BP is a reflection of increased resistance to flow of blood in the regions away from the heart especially the limbs. Both the upper (systolic) and the lower (diastolic) BP need to be kept normal. It should be ideally close to 120/80 mmHg. I think you need to consult your doctor.