When to call the Dr? (Blood pressure)

I was feeling dizzy after breakfast so I sat down for a minute and have tried to take my BP every 15 min (ish). My Dr told me anything over 140/90 is what she considers high...I keep getting close or one number high and the other okay. If it keeps up for another hour or so after resting and drinking water I was thinking maybe I'd call?

I'm not sure if that's a good plan or not but I dont want to overreact since it's so borderline. What would you do?