Can changes in my urine be a sign that I'm sick?

Urine can indeed provide clue that you may be developing or actually have certain health conditions.
Look at the color of your urine:

• If your urine is brown or dark, it could be a sign of liver disease, antibiotic usage, kidney failure, or use of muscle relaxants. If you regularly eat Fava beans or rhubarb urine could also be dark-colored.
• If your urine is pink or red, it could be a by-product of eating beets. Urine can also be red-tinged if you are menstruating heavily, but otherwise blood should not be found in your urine.
• Green urine can occur due to food coloring, or because you take medications such as Indocin. A urinary tract infection (UTI) can also cause urine to appear greenish. Try drinking water to see if the color disappears.

Some foods can make your urine odorous. But:

• if it smells like ammonia, you may be dehydrated.
• if it has a foul odor, it could be a sign of a bladder or kidney infection.
• if it has a sweet smell, it could be a sign of diabetes.

General appearance can also signal a problem: Urine that is consistently foamy or bubbly may be a sign of kidney disease.
Take note of changes in volume and frequency. Urinating more frequently but putting out the same volume may indicate a UTI or in men, an enlarged prostate. An increasing need to urinate larger volumes more frequently may indicate that you have diabetes.
If you experience any of these changes in your urine, see your doctor.