Varying low and high pulse rate and heart rate

Hi,
Im a healthy 19 year old female. I have a varying heart and pulse rate at rest. Sometimes my heart rate is as low as 66/ 39 with a pulse rate of 45 and sometimes its as high as 144/ 81 with a pulse of 70 and my pulse can be as high as 146. Im due to go to the doctor in a month as my heart rate was high last time i went. However having monitored my heart rate and pulse with a lood pressure monitior im now worried. Should i be concerned. Im an active, otherwise healthy individual :) I occasionally suffer from light headedness, tirdness and palpatations.
Thanks

[Jerry_NJ]

Before getting to your question, I note it appears you got an extra "0" in the age on your profile, it shows 109, I'd bet the stated 19 is closer to correct.

I'm not surprised you have some periods of lightheartedness with a BP of 66/39 (I think I'd simply pass out), especially with a HR of 45, at rest I assume.  Do I read your post correctly.

If feel alright it is unlikely that your are in serious trouble, but it is right to be checked out by your doctor.

[jimgreg]

if your heart blood p was 66/39 this would make you faint even before you got that low..my h.r. today was 49 at rest..daytime if not doing much its avg 65-70..you need  to gt checked asap!!!!!!!!!!!

[is_something_wrong]

I assume 66/39 and 144/81 are your blood pressure values.

Heart rates of 45, 70 and 146 are as far as I know, normal in healthy young women (if they increase with exercise or anxiety). Note, however, there are not necessarily any connections between heart rate and blood pressure - it is completely possible to have high blood pressure with low heart rate, and opposite.

A blood pressure of 66/39 is NOT normal. I think you should see your doctor earlier, but you can do some experiments - try to measure your blood pressure at rest, stand up, and measure it again a minute later. Try taking a quick walk - and measure again. The blood pressure is supposed to increase through those events. If it doesn't, mention it to your doctor.

Low blood pressure is not necessarily a bad thing - except if it doesn't increase properly with exercise, if makes you dizzy/faint, or if it's caused by inefficient heart output.