I'm getting different readings when taking my blood pressure and i have taken my medication?

Blood pressure : Your blood pressure runs in a range of normal with a lower range at night while you sleep. Stage 1 hypertension is classified by BP 140/90 or greater(either number); this is determined by a resting BP which is sitting quietly for at least 3 minutes before you take your reading. Always use an arm cuff and don't talk or wiggle while the machine is reading.

Can vary : As long as there are not marked differences in the readings would not worry. Your blood pressure can vary by a few points at various times of the day, and by how anxious you are when taking the reading. If the reading vary widely see your doctor.