Hello. Diagnosis of mild oral thrush usually can't be done only via pictures. A thorough medical and habit history followed by clinical examination is a must before diagnosis. It will be better to visit your nearest Oral Medicine and Radiology specialist, Oral and Maxillofacial Surgeon or Oral Pathologist (since specialities deal better which such conditions). If this is oral thrush then don't worry, It can be treated with oral and topical antifungals.
Health Tips
Meanwhile, avoid any oral habits like smoking, tobacco/supari chewing or drinking. Maintain oral hygiene. Avoid spicy or extremely hot food.