Okay, and should I still drink a lot as my thirst encourages me? I am wary of the dangers of drinking too much water...
Depending on body weight a healthy adult (with ready access to a toilet LOL) can safely drink up to 12 litres a day - the dangers of water poisoning occur when you drink too much too fast e.g. 6 liters in 20 minutes, I looked into this a few years ago when I was consuming 8-9 litres every night. Of course if you are drinking excessively you should get checked out and may need to take supplements to maintain your electrolyte levels.
The fact you are not urinating at night would suggest to me that it isn't diabetes, but your thirst would suggest it is - so dunno - go see a doctor.
edit......of course, if you are thirsty you should drink, but keep tabs on how much, and if you consider it excessive then go see a doctor (a lot of people believe the hype that says about 2 liters a day is "normal", it's not, many people need at least double this and more if it's hot or if they are on a restrictive diet).
edit 2.....drink plain water!! - coffee, tea, soft drinks, fruit juice, squash (even no added sugar stuff) - all should be avoided if you're having issues due to sugar, fake sugar (which apart from the calories has pretty much the same effect on blood sugar levels) and diuretic properties etc.