I normally have a blood pressure of 145/83 due to hypertension and heart disease. I am 63 years old, obese, and been taking medications of Losartan, hydrochlorothiazide, and pravastatin. Today, I have been dizzy, lightheaded, nauseated, and now my diastolic pressure has dropped down to 70-75 with the systolic remaining about the same. What do you think is going on?