I am male 25 i have blood pressure from past 1 month around 150/100 currently i am on meds and my blood pressure is controlled 110/70 but from past 1 month whenever i sit for half hour or stand for 10 minutes i feel pain tired and weakness in brain?

Blood pressure of 110/70 is really good for your age. Your brain is likely not getting used to that optimal blood pressure yet, give it some time to adjust. However, I could not rule out your blood pressure can be too low with prolonged sitting or standing due to pooled blood in the lower body part. I suggest checking BP at that time, if BP less than 100/60, your med can be reduces in half.