brenda finn was diagnosed with alopecia at 14 and lost all her hair .
she is now calling for medical tattooing to be made available on the nhs .
claims the £ 300 procedure would have saved her years of anxiety , depression and low self-esteem after condition left a target for bullies .
argues it would save the nhs money with alopecia patients who are reliant on expensive therapy or antidepressants .