My tongue has been swollen for a week I started to get patches of yellow thick coating on my tongue. And the other patches is just flesh what is wrong?

Thrush. The most common cause of the symptoms you describe is thrush. This is a yeast infection that typically occurs after prolonged or frequent antibiotic use but can happen for a variety of reasons, such as in patients who's immune system is weak and diabetics. Visit an ENT doctor. The treatment is usually a medicated mouthwash.
Hows your digestion? This sounds like geographic tongue but i dont like the swelling or the color. Yellow coloration is usually a digestive problem possibly weakened gall bladder. I would get this looked at soon.
See dentist. Please visit your dentist. It could be thrush, geographic tongue, or something else. If you do not get better within 10 days, please make an appointment for a clinical exam. Take care..
Geographic tongue. Obviously without pictures it is difficult to make a diagnosis. First go see your dentist. It sounds more like a flare up of geographic tongue and possible hairy tongue.