Cardiovascular :: Heavy Heart Beat And Trouble Sleeping

For three months now, I have been having strange problems with my heart.  I have been experiencing a (mostly intermittent) heavy heartbeat.  I'm a 170 lbs 5'10'' 23 year old male in fairly good health.  I work out regularly (mostly strength training).

It all started three months ago when I started noticing my heartbeat.  It felt most like palpitations, which I have had before, but mostly it was just an odd sensation.  Eventually, it turned into a really extremely heavy heartbeat.  When I would lift something light or just get up, it would feel like it was pounding out of my chest--really unsettling. 

About three or four days after the symptoms started, I started having extremely bizarre symptoms when I tried to go to sleep.  I would begin to drift off, and it would feel as though I was aware of my loss of consciousness.  I would feel really light headed and it just felt horrible, like I was going to pass out and die.

Before the symptoms started, the only thing that was different to my knowledge was that I changed my diet a bit.   I was trying to really gain some muscle.  I was working out 4 days on, 3 days off and increased my protein and carb intake.   I was having a protein shake after my workouts that included whey protein and creatine supplements.

As soon as the symptoms started, I immediately stopped everything--the intense workouts, the supplements, and the over-eating--I just went back to normal.  Oddly, the symptoms persisted, and only very gradually got better across three months.

I also decided to see a doctor initially, and had been to the ER two more times on top of that.  I also saw a cardiologist.  They all did blood tests, checked my thyroid, got a chest X-Ray, and did EKG's.  I even got an cardiac echo.  And nothing.  They told me I was 100% (heart and otherwise) healthy.

After three months, I am still having symptoms.  At times, my heart does seem to be beating normally, but about half the time or more it will kick start and just go crazy.  Sometimes for seemingly no reason, and other times when I begin significant psychical activity.  I would be able to live with this, but its the issues I have when trying to go to sleep that are the worst.  Just last night, it felt like as I was drifting off, my heart felt really heavy and "chunky" and almost felt like it was beating against my ribcage or something else and making my inside shake.  Really weird. (I have these symptoms during the day at times too).

I also have minor but bizarre pains that I can feel in the center of my chest, and sometimes in the top of my back.  I have experiences odd tingling sensations in my chest, arms, finger tips.  I also have sensations as if I get one really strong heartbeat.  I will be sitting doing something and feel a big beat and my chest that makes me jump almost.  I don't know if is a palpitation or what, but my palpitations have never felt like that before.
I am just really tired of dealing with this.  Because it has to do with my heart I can't ignore it, especially when it disrupts my sleep.  I have been told it could be anxiety but I just don't think so.  Symptoms come on randomly and when I am not even thinking about it.  I admit, I obsess over my heart a bit some days, but it is just because this problem seems so impossible.

I would like to think my diet is fairly decent, I do eat some garbage sometimes, but I try to get plenty of fruits, vegetables and water.  I don't drink much at all and have an occasional cup of coffee.  I still work out but only 3 days a week (m-w-f).  I don't do the protein or creatine anymore.  I don't have any other symptoms.