Brief Answer:
irritation of palate

Detailed Answer:
Hello,

Red dots on roof of mouth is commonly due to irritation of the soft palate. It can occur due to some reasons like:
eating very hot food
spicy food
irritation of salivary glands
alcohol
smoking

As you have mentioned that you are a non smoker simple irritation of soft palate is more likely than serious cancers. However I will suggest that you keep a watch on the dots. Most probably it will go away within a week. In the mean time avoid taking very hot and spicy food; avoid taking alcohol and use a antiseptic mouthwash. Should the symptoms worsen or persist beyond a week, visit to a local doctor/dentist is advisable.

Hope this answer helps.if you have any further query feel free to ask.

Regards
Dr. Shesh

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