Need to know detailed history before diagnosing anything. But looking at pictures it seems normal. Consult doctor online or offline for better guidance and treatment options. Maintaine good oral hygiene.

Hello. As your picture doesn't seem to give much of the information needed to get to a diagnosis, it will be better to get yourself clinically checked by an Oral and Maxillofacial Surgeon or a  General Dentist to able to tell you that is it something serious or not. But before that, it would also be beneficial to know whether you have had a history of frequent tongue biting or having any sharp edge of tooth constantly causing trauma to the sides of your tongue. Your picture and you noticing the same thing on both sides of your tongue aren't suggestive of anything alarming but it is best to get it checked clinically.