Hi
Bed humping is very common among youngsters.
It involves rubbing of one's genitals against bed mattress to experience orgasms.
You are doing it in privacy of your bedroom so its perfectly normal.
It does not ruin your teen years at all.
Next Steps
You have been doing it from a long time
So its time that you learn about other ways also.
You can take help of internet and various books.
Alternatively you can take a hobby like playing some sports and get your mind diverted
Health Tips
Try to get rid of this habit so that it helps in longer run.
In case of further queries please feel free to write back.
Thank you
Regards
Dr Prashik Meshram