I can't get my blood pressure to go down even with doubling my 3.125mg dose of carvedilol. will readings of 148/100 over the course of a week or two kill me?

Hypertension: I am not a fan of carvedilol as first line treatment of hypertension, unless you have accompanying heart failure,as the effective dose range is very wide from patient to patient. You are on a low dose. I don't think you're in any danger with that blood pressure, but notify your MD who may want to increase the dosage of carvedilol, add a diuretic, Ace inhibitor,ARB or calcium channel blocker.