Need help understanding my Blood Pressure?

Hi im 18 and iv been smoking since i was 15 for this last year iv been smoking about a 30 pack a day so i think its time to quit, im cutting down to 4 smokes a day to start with and will be fully stopping after 1 week, now iv been recording my Systolic and Diastolic levels but cant really understand them to well, from the start day my readings were (139)SYS and (65)DIA, im now on day 5 and my reading are (105)SYS and (54)DIA, my question is has my SYS and or DIA drooped to a dangerous level or is this a better level? i wish i could have worded this better but hope someone understands what im asking :) , anyways any help would be good :)