Starting yesterday morning, I decided to quit drinking soda altogether. I'd had some pretty bad heartburn lately, so for my own comfort and health, it seemed prudent to eliminate the constant source of acid from my diet. As this was the sole source of caffeine in my diet, this also meant though that I was simultaneously going cold turkey on that substance as well.
That has made this a whole lot of no fun.
First off, I'm sleepy as heck right now. I've been living with an almost constant flow of caffeine for years, so dropping off hard has left me not super-alert. It's the sort of thing that happens when you cut a stimulant out after this long though -- it will take my body a little while to adjust and adapt.
Secondly, I am without the psychological comfort of grabbing a Diet Coke, hearing the pressure shift as I open it, and holding it in my hand. I'm compensating a little with bottled water, but half a dozen times yesterday I found myself scrounging the kitchen, realizing that what I really wanted was a soda that wasn't there.
It helps that there isn't any caffeinated soda in the apartment right now.
The headaches haven't kicked in yet (as they have most of the other times I tried quitting caffeine), so I'm looking forward to those. I can tell I'm less focused -- you have no idea how hard it is for me to type this out. I've had several sentences that I've had to reread multiple times to make sure they made sense (this one included). In a few days I'll be back to normal, but I'm nowhere near that stage yet.
The next few days are going to be a whole lot of no fun, really.
I quit caffeine back in February and feel much better for it. I had headaches for a while and slept way too much but eventually withdrawal subsided and I started feeling so much better all the time. Keep going, you can do it too!
I stopped drinking coffee for the same stomach reasons. Good luck kicking the caffeine addiction as well as the Diet Coke. The way you describe it with the pressure hiss reminds me of when I quit smoking. Hancock in their and good luck.
Best of luck. I know it sucks, and the craving for the sweet, sugary goodness can be pretty irresistible. Six months ago, I quit my soda habit too. Whenever I had spicy food from the food cart, I craved a Coke badly. Mostly because I was tired of having 8 cavities every time I went to the dentist, and now I don't have dental insurance anymore, so time to start taking care of my teeth and weight. I also just quit drinking frappuccinos after my last week of grad school, so I'm also coming off that caffeine/sugar high.
Switching to bottled water is a really good step, and the focus issue sounds familiar. I've been trying to do daily games on Lumosity instead (http://www.lumosity.com) to improve concentration. Not sure how much it really helps, but it kinda makes me feel better.