A few questions about heart rate and blood pressure

Hello
I have a few questions about my heart rate and pressure. I am 42 yrs old, take vitamins, iron due to slight anemia, flexeril and xanax as needed for pain. I suffer from fibromyalgia, osteoarthritis, DDD, spinal stenosis in neck and lumbar spine, and bad disks.
I do not have panic attacks, but sometimes feel anxious. I get that, rush, rush, rush gotta go feeling, can't sit still. (but not all the time) RIght now I am not walking or exercising. I generally stay busy in my home. ( I stay at home too)
My heart rate over the last 3 to 5 years has been acting funny. I am usually around 100 and get tachy really easy. My blood pressure can go from being 110/77 in the am to 139/90s during the day. No caffeine other than chocolate every once in a while.
I can be sitting and get up and my heart feels like it starts pounding, and it can do this even with moving a little bit...almost like it's unstable. I have been in the 100 to 115 range all day, the bam tonight im 77 to 80s. It seems like when my blood pressure is 120s over 80s my heart rate is high. Then when my bp is high, 139/90 my heart rate was 80s. It changes.
IF my blood pressure is normal when relaxed or first thing in the am below normal, the other day 112/77 to 139/90 during the day, is this considered hbp?
I went to md the other day. HR was 134. I may have been anxious..didn't feel anxious. I even took half a xanax 45 mins before the appt.
SInce I have not been walking for several months, could my heart just be out of shape? I hate feeling my heart pounding in my chest.
I am 5ft 3.5 and 163 lbs so I am about 25? lbs over weight. I also do not smoke or drink. My cholesterol was 150 about 8 mths ago, and lipids were good.

thanks for any help or just your 2 cents!! lol
karen

Have you ever heard of POTS and have you been tested for it? I had the same type symptoms and it took forever to find the right doctor who finally diagnosed it.