A pale white tongue is usually due to lower iron content in the blood. it could also be a cause of organ(lung and colon) related problems. i would suggest you to get a complete blood picture done and please visit a dentist soon. Preferably an oral pathologist

White tongue can be due to multiple reasons and the right cause can be delineated after a proper clinical examination and detailed history. The right treatment can be suggested after the right diagnosis has been made, and this could vary from a simple coated tongue to some fungal infection or any dietary deficiency. And all these are tentative suggestions based on the simple verbal description without a look at the clinical condition of the tongue. The least you can do is make sure that you clean your tongue using your toothbrush after every time you brush your teeth. Make sure not to use a tongue cleaner whether it is plastic or metallic or wooden because it causes more harm than good. To the best of my understanding, frequent urination is unlikely to be related to the tongue problem and you need to visit a physician for the same. Regards.