When to be Concerned About Low Blood Pressure?

When should I be concerned about low blood pressure? I recently stopped taking Cymbalta, and my blood pressure has dropped quite a bit. It seems to get lower and lower every time I check it. Last time I checked (last night) it was 99/65. I know the normal range ends at 90/60. I'm not there yet, but I do frequently black out when I stand up after sitting or laying for a long time. I've always had low blood pressure, but it never flags as low at the doc because I have extreme medical anxiety and my blood pressure reads a healthy number in the middle of the normal range for the duration of the appointment because im nervous. I've never seen my numbers dip under 90/60, but I'm concerned about the blacking out, especially since I'm off the med that regulated it, and it keep dropping. When should I start being concerned and/or seeking help. Should I be recording numbers at certain intervals? I wouldn't worry about it if I wasn't blacking out worse and worse every day