What Causes Elevated BP And Heart Palpitations After Taking Prazosin?

Hello doctor, could you please tell me, if it is possible, taking Prazosin for high blood pressure, actually makes it worse? I feel very bad after taking 1 mg of Prazosin and recently I started checking my blood pressure with automatic monitor and after 2 hours(morning) of taking Prazosin, blood pressure is 177/100, pulse 100. In the afternoon is lower, 145/9o, pulse 99 or 90. In the evening, when I take second Prazosin, blood pressure goes high again. Also, my heart beat is very fast and pounding. I would like to stop taking it and don t know if can stop it or continue with smaller dose. How much smaller and for how long.