Well let me tell you it doesn't matter if you are 15, 20, 40 Or 60.  It is all about the quality of your life and how you live it.  Yes being an adult does tend to suck the green hairy monkey balls but it does have its advantages as well.  It is just up to you whether you focus on the bad things or the good.  I hope that your new age comes with many good times and hopefully not too many of the bad.  Damn I sound like a greeting card.  Lmao.