Fix my Underbite

I'm a 16 year old teenager and my dad can't afford the money to buy braces/fix my jaw so I don't know how I'll be able to get the money to get braces, it will probably be until when I'm an adult where it is most probably too late as my jaw becomes skeletal, right? My dad is too stubborn to be concerned about my jaw issues hence I don't want him to be involved... I don't know what to do and I'm scared as I've some symptoms of TMJ (popping sound every time I open jaw and jaw pain) Please help me