Tried deep concentrated breathing meditation for the first time. Was overly enthusiastic about it, whatever thought came into my head was washed away by my focus on the next breath. I was attempting to record how many times in 15 minutes I'd get distracted while meditating. I was breathing really intensely and breathes became quicker as to enhance focus, most of my body was tingling. Around the 11 minute mark my arms were raised in awkward positions and curled up like I had received brain damage and I stopped early since I dropped my lantern. My arms could move after a few minutes, but I'm still a little shaky. Did you guys ever have anything similar happen? Could this be attributed to some sort of cardiovascular issue?