At my appointment 2 weeks ago, my blood pressure was reading kinda high at 140/80, they basically told me to relax and they'll check me again this week. Today I went and it was 137/81 and the nurse asked me if i have high bp, i told her about my last appt, so she re-tested me but told me to hold my arm up high over my head and this time it was 105/60, is this an accurate way to test bp???!