I have been getting dull cramps in the bottom of my belly with head aches and a sickly taste in my mouth its been like this for nearly 2weeks now?

See your doctor: Problems like these can only be correctly handled by your doctor in person. He/she needs to listen to you, perform an examination and possibly run labs or other tests. That's the only way he/she can find out what's going on and what to do about it.

Sinus infection?: You may have a sinus infection if the taste is foul or there is drainage down the back of your throat. Alternatively it could be acid reflux if the taste is bitter / sour. See your doctor for a check up