My dream job is an interior designer....is it a good job to dream about or could it be a dream come true?

Okayy.....ive have wanted not be alot of different things when i get older but now i am pretty storng about how feel about this one. Im a reshman in high school...im curretnyl taking a basic art cl & next year taking drawing. is that a good background so far ot start with? Do you have any suggestions on courses i should take in high school to preapre? what about all the skills needed for the job? good colleges to strive for? My gma always everytime i say oo i wanna be this when i grow up she discourges me saying oo like that really hard you cant do that.....or like your afraid of blood thatll never work. it gets me discourged toward my dream . Also how much schooling do you need? how much pat do they get & will there be a high demand for it by the time i gradute. i gradture high school in 2012. THANK YOU SOOOOOOOOOOOOOOOOO MUCH!!!