Will my hair be completely ruined if I get it professionaly dyed from black to blonde?:confused:

No, not if you get a good professional and us a really good conditioner.

No... but make sure that they know what they're doing and are very qualified.

Bleaching your hair from black to blonde may cause some potential damage to your hair. This is called a double process, bleaching and toning. A double process consists of lightening the hair pigment to a yellow or pale stage and then putting a toner. This process should only be attempted by a professional. Professional hairstylists have worked with bleach, so most likely they will be careful not to over-process your hair. After the coloring process is done, they will also apply a protein conditioner to keep your hair healthy and strong.

No. It'll be fine as long as you get it done by a professional. Some of the do-it-yourself kits have harmful chemichals in them (for the bleach.) After make sure to use shampoo and conditioner made for colored hair.