Hi. i have white spots on my tongue . last few days other hearts to swallow . what can it be?

Infection: It could be a yeast infection with the white spots. These can have underlying red sores and can cause burning sensations or general soreness. But when ill with some viruses, you can have a coated tongue. Other symptoms to follow like glands swelling, swallowing difficulties, etc. See your md or visit your dentist for help.

Few possibilities: Depending on the nature of the white spots (size, location, flat/raised, quantity), it is likely either a fungal infection such as candida (commonly), or possibly apthous ulcers. A dentist or physician should be able to identify the cause and provide appropriate treatment. If it is a fungal infection you would need medication. If ulcers, it is self limiting but medication will help alleviate pain.