Not enough water and I can feel the difference!

Last week I posted a question about drinking too much water on the message boards. The general consensus was that you can drink too much water, but that it appeared the amount I was drinking was not too much, especially since it wasn't due to extreme thirst. 
To catch you up, I am finding that I am drinking roughly 104-130 ounces a day. The low end on the days I don't work out, the high end on days I do work out. I make sure to include something like gatorade or coconut water on the day I work out as well to help replenish the electrolytes in my body. 
This past week, Friday included, I was not even drinking half that in water! While less than 50 ounces a day in water for some is not that big of a deal, before I started drinking 104+ ounces on a daily basis, I was still drinking at least 64+ ounces in a day. I could really tell the difference this weekend not having enough water. Not only was I not peeing as often (the only positive), I had a very mild headache for much of the time and felt a bit more sluggish. Overall, it was not so great. This was also compounded by drinking coffee and alcohol. 
I didn't have the water bottle with me, which is what made getting my water difficult. So much easier when the bottle is with me! I am pretty easy going with water and have no problems with tap water (especially since that is typically what is in many bottled waters). 
Today I am back to getting my water, without even thinking about it, since the bottle is with me.