I want to learn to sing but….?

I can play the piano and guitar but i want to learn to sing. Im inspired by gary barlow and robbie williams :P. But. When i say i should learn to sing to my family they just take it as a joke, and i think it would be a bit embarrising practicing at home, when i havent had lessons or my first few lessons. Im a 14 yr old male and im not really sure if my voice has dropped yet, cause it doesnt sound deep, but then again some adult voices arent that deep, so i dont want to sqeek when i go high, or when my voice drops id have to pratice lots again. (Also i want to be famous in music, and yes i know not many people make it big )

Any advice :S
I would practice myself but if would find it a tad embarrising, so id do it alone, but thats not often :(

When I’m older I want to be a rockstar.Am I wasting my time thinking about a silly fantasy that wont come true?

I am 14. My idols/heros are all rock stars.
David Bowie, Mick Jagger, Slash, Keith Richards, Steven Tyler, etc…
I play guitar. I’ve been playing for 1 year and I practice like hell. I am going on to grade three in Easter next year. And I have just done debut a month ago and got distinction (If I may say so). :)
anyway, for the past year I have been dreaming of being a rock star like my heros. this may be a little awkward seeing as I am female. but, hey, there was tina turner. and janis joplin.
I am in a band. 2 bands actually. I play bass. and a bit of guitar. but they count for almost absolutley nothing seeing as they are school bands and all we do is play at school concerts. although one of the bands almost got a gig at a pub but the drummer couldn’t make it.
The reason I say rockstar, rather than musician, isn’t because of the money or fame. Well. I guess you could say that… anyway, the reason I said rockstar is because I love playing to crowds. I love the feeling of it. I did one school concert with the ever-so-radical-school band and there was maybe 200-300 people in the room and it was amazing. even though they all just sat their eating their crisps. it was still amazing.
Am I wasting my life? should I concentrate more on the more boring lessons so that I can have a boring, normal job when I am older?
I just don’t want to live the way everyone else lives. drive into work. sit in an office all day. paperwork. drive home. shower. bed. every day. that just seems a waste of a living.
when I get out of school. I’ll be seventeen. I want to go to college. And I plan to get a band started then. but, who knows. this is like four years away. things will have changed.
should I just give up now, and realise that this is never going to happen? even though I want it more than the whole world?
I want to bring good music back. God knows if I can do that. but I want to try, all the same.
do you think i have a chance? or am I just another 14 year old who is dreaming about something that will never happen?
I know rock stars don’t live perfect lives. when did I say they did?
I just want to make music and perform music as a career.