It seems I can crack my back a lot by simply arching back on upper back or leaning to right with upper back.(not left though) and it dont hurt. Also when I say fall asleep then wake up in few hours my heart area feels different usually and in throat area too or diaphram its maybe called.i notice im always thinking about my heart wanting it to be healthy. (Because I had a paracardial effusion of heart in 2003 due to laying in hospital bed for so long due to mmotorcycle accident) on weekdays I mostly lay down after work watching tv or movies. Im 6ft 1. 175lbs athletic looking 32yr old but look 24. I dont smoke or drink, my blood pressure is usually good, I take lot of good vitamins. No matter if im eating real healthy only or junk food, or juice extracting raw fruits and veggies the feelings are always same. I had ekg test for physical for new job last week and all test went good, even the breath out test to mesure lung capacity which I got 81 really trying but not trying hard I got 73. I do sometimes get anxiety which then I would take a .25 zanax. Sometimes I sit and think to myself wow im still breathing , or wow my heart keeps beating like i need reassurance that im alive. I just want to be as healthy as I can. Which is why I have 8stage drinking water system that has alkaline filter to raise ph, during physical she said my urine was alkaline. One vitamin that helps alkalinity is sun chlorella. Sometimes I have a habbit while exhaling/inhaling I can hold my breathe and press or tighten my left chest and will hear maybe cartalige mmaking sounds or something but told my doctor I do it and didnt want it being bad for heart, and he said its fine. Like im in hot bath now relaxing because I didnt feel right going to bed, so I took a .25 zanax and hot bath to try to feel better to then fall asleep soon. I think whatever builds, up in spine that enables me to crack back every 20 min leaning right or back may have to do with some of this maybe. Upper back is not in pain though. Every so often my keft chest would h7rt pushing on it with what ever muscles internally that due it and I felt that was just hear burn and or anxiety symtom because id take something for heart burn and it would go away in morning. Have not had that in like 6mth or more. I just wish I could get my mind off my heart.