Forced to wear a diaper?

-i am a 15 year old boy and my mother and father took me out to go shopping and they went down the baby section and they pick up nappies and i asked who are they for and they said me. i was puzzled and i said why they said i am now going to wear a nappy to bed and to school and out with Friends i don't know what to do has anyone got suggestionstried to really ask them WHY ?