What does oral thrush look like ? is it sore ?

Can be: Oral thrush is white and covers part or the entire mouth/throat area. It can be rubbed off but this is not recommended. An anti fungal prescription will clear up the thrust. Consult with your doctor.

White Plaques: Thrush is caused by a yeast called candida.. Many babies get thrush in the mouth in the first few weeks/months of life. Presents as white, irregularly shaped patches that coat the inside of the lips and cheeks and sometimes tongue. Thrush can cause minor discomfort. Increased risk in older children/adults with oral antibiotic use.

White coat: Yes, it can be painful and usually gives the tongue a whitish appearance.