Brief medical history (thought this may help rule things out): chronic fatigue, anemia, major depression, GAD. Bad neck.
Recent symptoms/story: For a while now my heart rate has been quite elevated, even on resting. It is rarely under 100 bpm, tonight it is sitting at 115 beats/minute. Whenever I stand up, my heart starts to really thump and pound to the point it's uncomfortable. It sometimes skips as well. My blood pressure has always stayed the textbook 120/80, so until now I haven't been too concerned.
The past week I have spent a bit of time on the computer, which I think may be half the problem, yet I have only rarely experienced this in the past but now it has been a constant thing for the past week or so. When I stand up, there is a huge pressure in the back of the head. My heart begins thumping really fast and hard, and my hearing is distorted, which is quite frightening. It's like a pulsating whooshing in my ears.
Tonight I took my BP, which is usually perfect, but it was sitting at 100/60. This happened approx. 5 minutes after standing and is a very low reading for me.
I admit I do not exercise nearly enough as I should. However I find exercise extremely painful, my heart gets so fast and thumping and I get faint so it kind of scares me to exercise. Now I'm getting way too unfit and this can only contribute to the problem 
Could the elevated heart rate and low blood pressure be related? Anyone experienced these symptoms?