Question about dog tags?

My older brother who was a airforce tech sarge bought me dog tags from his base now there just like military ones with all my ssn blood type and stuff but I looked at them and they have the AF on them now I haven't wore them cause I don't want to dis respect them cause I'm not in the airforce yet I'm leaving in July for air force would it be wrong to wear them also my brother was killed so I kinda want to wear them but not sure if I should