I am taking calcium channel blocker- eslo 2.5mg/day) since 2005. how to know if my htn is over-treated?

Bp monitoring: well you can buy an otc BP machine and check your blood pressure several times a week to see if your BP is normal or too low. The dose you are taking is a low dose but either you and/or your doctor should be checking it on a regular basis to see that the blood pressure is in a normal range

B/P and symptoms: Starting with the obvious, if your B/P is in a healthy range when checked and you feel fine, it's probably not being over-treated. On the other hand, if you feel weak, dizzy or lightheaded when you go from lying down to sitting or from sitting to standing (even if your resting B/P is in the normal range), this needs further evaluation.