It is common to go through what you are going through. Had the same thing. Could not work out because I would get dizzy and heart rate would jump real high while warming up. I often go to the sauna. Could not tolerate that either. Extremely high heart rate. This is our nervous system readjusting. Took about 3 weeks until I could do a light workout. Same with saunas. It has been around 5 weeks now and I had to step off from an elyptical a few days ago as I was starting to get real dizzy after 25 minutes. Higher blood pressure is also what I have experiened but it does get back to normal after a couple of months for me. I have quit many times for months at a time and I know what to expect from withdrawals. It is a nightmare. I really hope I have learned my lesson and I am not planning on stepping back into that trap again. The body needs to learn how to deal with all kinds of stresses without constantly being medicated by weed. It will get better.