Okay, I myself have been dieting for the past three months and I can tell you some really useful stuff that I've learnt so far. This of course if you really care for my advice, because asking if cold hands means vasoconstriction sounds kinda like trolling. That being said, take note:
1- Your body burns both fat and muscle when resorting to it's reserves, in fact muscle tissue is much more easily available and better energy burn so if you restrict your calories in excess you will loose more muscle weight (which is always good weight) than fat weight.
2- It depends on your size but if you eat under ~1400 cals/24hs your body will think you're in a famine which means that no matter what you do you will start gaining weight even from one apple a day (your body will use the minimum amount of energy for anything you do and start saving EVERYTHING)
3- caffeine ups the glycemic index of the food you eat (google glycemic index or GI), metabolising what you eat into higher amounts of carbs (I.E. not good). So if you want to get thin/healthier/increase muscle mass, then no caffeine for you.
4- You need to drink 2 litres of water a day in a normal calorie intake diet (around 2000 cals if you don't move your butt, around 2500 if you move it 3 times a week, around 3500 if you move it everyday) - That is to maintain your weight. Most of the water you actually get into your body comes from food, not from what you drink, so if you are eating less than what you need (i.e. hipocaloric diet (i.e trying to loose weight)) you will have to drink MORE than 2 litres of water a day or you WILL damage your kidneys. No kidding, you WILL damage your kidneys.
5- eat before you exercise or you won't loose as much weight nor make the most out of the session nor feel as good after.
6- healthy and big muscles burn fat just to breath (that means 24/7) so don't just do cardio, get yourself a good anaerobic routine and DO IT after you do cardio, it's just as important to be both healthy and thin.
7- move. 1 hour of cardio a day plus 23 hours of browsing the internet will not make for a good body, walk everywhere and make up excuses to go to places, get to know your city.
8- a balanced diet will do much more and much faster than any vegan, atkins or whatever that you might find online. eat absolutely everything, but just a little.
9- counting calories can be a good thing, to stop you from eating too much and to stop you from eating too little.
I'm not sure if what you're trying to do is loose weight but a lot of this is good for more than that. I started for loosing weight and now I'm loving exercise and being fit that I wouldn't stop for anything.
I lost 22 pounds in 2 months and that's more than 22 fat pounds because I also gained a lot of muscle tissue.
Drink water. Good luck.
PS the urine thing is dehydration (both from lack of water plus extra urination from the coffee. ugly shit man take care of yourself.)