Hi. Eating rough food can be a reason it. Also run a finger around the tongue side of your teeth to check for sharp edges that may be bruising your tongue.
Also check in the mirror for ulcers on the tongue. You can use a gel such as Dologel or Oraways on them. Should be fine in 2-3 days. If they still persist kindly visit a dentist for review.
Answered2017-06-03 06:31:58
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