hey Sam
I know exactly how you feel(its so similiar to how i was) i was 17 when i first started being anixous. I was the same as you...always dealing with other people's problems but i never could tell anyone about mine! its now 3 years on and only now do my friends know everything!(try to let them know ur abit:(
I know now the reason i had problems was change i didnt know what direction to go in and i felt pressure from every side! and like you i watched my life away (i still do now sometimes), i always wished one day everything would be fine!somehow like magic my worries would disappear!bet thats how u feel!?
Ok so advice keep a diary i do! its a great release and no one has to see it but you! and i think you should tell ur parents(well at least your mum) My mum has been amazing and it will really help you, even if its just taking you to the doctors! think about it they are probably more worried now cos u wouldnt tell them whats up!
Also i used to go out alot when i was ur age and when i started panicing i would still go but drink alot!not a good idea! try not to drink when ur feeling low it only makes you feel worse!
i hope this help (and makes sense), you are not alone remember that! try everyday do something that makes you smile, even just alittle thing will make u feel better!
Love Jenny xx