How often can I dye my hair?

Of course, dying it often and blowing drying you hair everyday will definitley cause damage to the hair.
Infact I have curly hair and I used to always blow dry it.. Then I stopped because it was never growing longer due to all the split ends and dryness.

So I now leave it curly.. Curly hair is great
And occasionally I blow dry it, for maybe special occassions and it looks a lot healthier.
Why do you need to blow dry every every day? Do you wash your hair every day? That may be a reason why your dye only lasted 2 weeks.. I'm guessing!
Or Maybe because it was a semi-permenant colour instead of permenant?

I used to also dye my hair my redish, to black and vice versa and it always lasted 4 - 6 weeks.

RICKJ
This is another thread that is not appearing under my profile, while it should be as I replied to it.
BUT as I wrote this - it suddenly appeared on my profile

I wash it everyday. It gets oily if I don't. I was thinking of trying to wash it every other day, but I blow it dry because then I straighten it and blowing it dry makes it easier. I guess twice the heat isn't necessary and I could just straighten it and not blow it dry. My hair isn't pretty curly...I do like curly hair, but mine isn't the good curly, it's the gross curly.

And I'm sure it was permanent dye. =)

Twice the heat on your hair is definitley not good.
What I would do, if you want to wash your hair everyday, do that but don't blow dry, pull it back and blow dry just your fringe that's what I do to save damaging my hair.
And when you wash your hair try not to use so much conditioner, use it on your hair tips only, that may save your hair being to oily.

Most permanent color uses peroxide (10 to 40 vol.) and ammonia. Permanent color will last until you cut it out or until you get it re-colored. They require maintenance to new hair growth after 4 to 6 weeks. If you want the color to last without fading, apply a deep conditioning treatment to your hair a few days before coloring. The better conditioned your hair is, the easier the color will take and the longer it will last. You can also use shampoos and conditioners that are designed for color treated hair. You should consider going to the salon to have your hair colored. When you have your hair professional done, the hairstylist will give you tips on how to maintain the color by yourself.

Use a blow dryer with an attachment to help focus and direct air flow and reduce frizz. When Using dryers, make sure you keep your dryer moving at all times to prevent heat damage. Apply straightening balm or serum to damp hair, then you're going to take a round brush and beginning at the roots, gently pull the brush through the hair to the ends while you blow-dry it. If you want sleek straight hair, you must dry the hair until it's completely dry. Then, use a flat iron all over the hair and add a little of hair wax or serum to finish the look.

Hair has a limit on how many times you can dye it, each time you do it is a chemical process and should not be repeated over and over again. Try using semi-permanent colours as these are conditioner based and so are really good for your hair, also try to get it cut every 6 weeks as this will remove some of the dye.

I have had the same problems as you. I've dyed my hair many times, and many different colors, which does take a toll. You should only dye your hair every 4-6 weeks. But even then I found that my hair was becoming much more frizzy. I recently just cut a large amount of my hair off, to kind of start over. Since then I have dyed it a redish brown and like you, wanted to get rid of the red. I find that no matter what I use the brown quickly fades and the red soon appears. I even used a blue base dye, and not red. Anyway I had a hair stylist tell me that if I stripped my hair (which is like bleaching it so that its very white) I could dye any color over it, and it would last. I'm not sure if that's something you would be willing to try or not. I know you can get it professionaly done, or get the hair stripper and a beauty supply store. It is damaging to the hair, but I think in the long run it could be worth it. You won't have that red or black or any color for that matter, trying to come trough. They also sell color protecting conditioners at the beauty supply store, which seem to help me a lot. There are some that actually have a hint of color in them, and there are others (which I use) that just somehow protect against fading of your dye, and will work for any color. They smell great and are great at keeping my hair moist. I wash my hair every day like you. And honestly I noticed that my color lasted almost twice as long while using this. You may want to try this first, get some and start using right away the next time you dye your hair.

Joo zee, ze problemz is not wit ze hair per se chikacita. It is wit ze attitude zat joo take wit ze hair.

Pendeja.

Liar.