This has probably happened to a lot of Ты because of taking notes in class.
Have Ты ever got a little blister или callus because of Письмо too much on your finger? It's normal. All it is is a small callus from the pen applying a bit too much pressure или rubbing for too long against your skin.
Calluses are not dangerous, but they aren't pretty either. All people who practice something with their hands all the time get them. Playing the гитара или even cooking a lot can result in calluses.
So Ты have some calluses and Ты want to get rid of them. Fine. Use pens that have a little padding and try not to push down so hard on the pen.
Ты can also do a treatment to get rid of calluses. Put your hands in warm water with лимон for 10 минуты and let them soak. Then dry them off and apply creams или миндальный, миндаль oil to the callus. Use hand cream daily and Ты will see a difference.
If the callus hurts and does not go away then ask your parents about it. Lol