Terriblyconcerned

Hello, I just started working overnight 2 nights ago tonight is my third. On the first day I noticed my urine has been a very weird color.. it's kind of hard to explain.. it's almost like a dark brown but not quite brown.. it has a weird color.. when I get home and sleep my urine is back to normal.. I thought it might be dehydration but I'm not sure because the start of tonight my urine was fine about 3 hours into my shift it turned the weird color again even though I drank about a litre of water.. but my mouth is contantly dry and I do sweat a bit while working because he requires a lot of physical activity that my body isn't used to not to mention it is hot in the building.. could it be just something simple like dehydration? I don't experience any pain or anything it's just a weird color that I've never seen my urine look like.. I don't know if this is the right section for this.. any help is appreciated. I'm hoping it's just my body adjusting to overnight work.. I'm very worried.