Thanks for putting up your question on Just Answer.
The most common injury on the roof of your mouth (palate) is a thermal burn. This happens when something very hot ( most commonly a pizza slice) or very cold touches the mucous membrane of the palate, causing loss of surface epithelium and resulting in a raw area.
This feels different when touched by the tongue and it is not really painful.
Most probably this is what has happened to you. Other than this, there are several possibilites that can cause blister formation on the palate, but none of them are really serious.
Since you noticed it just two days ago, I suggest you wait for 5 more days before visitng a dentist
Do not take any mouthwash, as it may irritate the raw area of the mucosa. Avoid food of extreme temperatures.
Hope this answers your question. Feel free to contact me again for more information.
I wish you a speedy recovery !!!
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