Tribenzor

Hello all, I am new to your forum.  My primary md put me on Tribenzor to control high blood pressure about a month ago and it has been working well.  Within the last few days, my pulse has been racing after any type of physical activity.  I did some internet research and thought I might be dehyrated, as Tribenzor is a diuretic and I probably haven't been drinking enough.  My dr thinks it's more of an anxiety issue.  Has anyone had a similar experience?