How long do I have to wait to dye it again?

I was hoping someone could help me with some suggestions about how long one should wait before dyeing their hair at home again. Ive been dyeing my hair for years and years (usually a lighter blonde than my natural colour) but recently I tried dyeing my hair back to what it would normally look like, a dark blonde. 

I don't think its necessary to wait that long.  I always waited 2 days so the scalp oils could build up a little to protect the scalp from the chemicals, but waiting any longer isn't going to change anything about your hair. 

Do realize though, that what you're doing is very complicated.  You removed all the colors from your hair that would counter the base colors in any darker dye you would put over it.  The chances of you getting an exact color you may want at this point are slim without going to a pro.  It is definitely possible to get a natural, non-gray looking color, but it just may not be exactly the color you're hoping for, and it is likely to look a bit dull, as all the shine in hair is mostly stripped out once you go white.

Since your hair is already gray, I'm assuming you used a dye with a violet base?  I couldn't predict what using red over it at this point would do (but if you had chosen red the first time, it likely would have gone too bright, or even pink or peach).   It may be too late to use a protein filler, since you want to counteract that gray....hopefully a pro will respond on that point, as I'm not a pro and am not sure.

Going to a pro is going to be the easiest and most relaxing way to do it.  If you really want to do it yourself, you will probably have to dye it twice using opposing base colors to get a natural looking color.  (Use a red, then if it comes out too red or too bright (it likely will), use a color over it that has a green base...blue if you can't find green).   Test strand absolutely, not only to be sure you want to tackle this, but to get your timing right if you do, as this is a bit unpredictable.  If you want to go lighter blonde instead, choose one with a gold base if you can find it to counter the violet gray in your hair.  Again, test strand, and I do really suggest going to a pro instead.

okay i am fifteen and i went and got my hair done at a salon and the lady messed it up and i HATE it so much! i got it done on friday and we tried calling her but she wont answer we left messages im not going there ever again but i was wondering if it was to soon for me to die my hair at home?