Oh, I can relate!!! 2014 has been a crappy year for me, as well. Like you, I was fine before this started. My health anxiety started in January, as well. For me it was a combination of several factors which I believe caused me to essentially "breakdown" -- the LONG winter (I live in New England), not having a vehicle to leave the house (my husband & I have been sharing a vehicle for 3 years now & where we live is very rural), my husband's job (rarely allowed to take time off -- this is probably the biggest part of my "breakdown"), trying to start a business (which ran into several snags that slowed us down), financial issues, AND the whole family getting nasty colds (our then 18 month old had a fever on & off, which meant lots of lost sleep & carrying her around constantly, which caused me to strain muscles in my chest, back, shoulders & neck, which caused my first health-related concern: chest pain). Ugh! Just writing that makes me exhausted. It was not a good time!
The chest pains were just strained muscles, but since then I've worried about various illnesses & health concerns. I've been to like 4 doctors & to the ER twice for various things -- everything always comes back normal, one doctor joked I was "too healthy". Everything always comes back to muscle-related stuff, which I now think is mostly stress-related. I have days where I feel normal again, but then will have a bad day (or two or more) where I have so many of the symptoms you have. That built up adrenaline feeling (which you described perfectly!) is the worst!!! One time when I was having it, I was at my parents' & I got on their elliptical for a few minutes -- it helped! So I'm trying to exercise more & I've been doing yoga stretches to target specific areas that tighten up on me. That definitely helps. I do my little routine every morning no matter what. Even with kids climbing on me, the dog barking at the cat (so relaxing!), snot running constantly from my seasonal allergies, etc. -- I push myself to keep going! Never thought I'd be the type of person to stick with an exercise routine like that, but it's been several weeks & I'm not sick of it.
Anyway, just wanted to let you know I understand where you're coming from. I thought I'd be better by now, too. Keep taking it day by day, find things that make you happy & keep you going. I know it's hard. There are days you just want to give up & cry. But keep going...