I would say you are experiencing growth but maybe it has come to fast and is uncomfortable for you.
When you have unbalanced energy the heart seems to suffer the most from it.
The old Daoists and Buddhists also used herbs to stabilze such conditions called "Shen Stabilizing" and you could find references to such things at www.dragonherbs.com
I also use to meditate many hours a day and found that my kidneys went weak because of it. Meditation should be balanced with active exercises.
Hope that helps.
Jeff
