In the morning i've been coughing up dark brownish mucus. its mostly clear with dark brown spots sometimes its more than just spots its more like a brown gray blob.

Bronchitis: Most probanly is a bronchitis go to your doctor to get treatment. Good Luck!

For how long?: How long have you had this? Do you have any other symptoms? Do you smoke? Sometimes a recent change in sputum color can be due to bronchitis, an infection which often responds nicely to antibiotics. So get checked. Avoid perfumes (scented detergents, candles, soaps), smoke, aerosols, as they can cause or prolong irritation to the lining of your whole respiratory tract.

Are you a smoker?: If so then the chances of this being related to smoking related lung disease are higher. Either way, this is not normal. You may have post nasal drip as well. I suggest you see a doctor in person about this issue. You need a complete history and physical exam, probably a chest X-ray at a minimum. If this is on the heels of a recent cold or flu you may have bronchitis. Don't delay in seeking eval.