I Think That I May Have Pica And Or Iron-deficiency

I think that I may have pica and or iron-deficiency anemia ... I'm a 14 year old girl . I occasionally eat dirt or sand , but it has to be a specific texture or "kind" . And I consistently eat chalk . This started when I was in 6th grade , with me mostly eating sand and dirt , and it has progressed to me eating less of that and chalk nearly everyday ( I'm in 9th grade now ) . How do I stop ?