Could the change of the mole on my arm be serious? recently a very small mole on my arm has become darker and smaller. it has a small red ring around it. it doesn't hurt at all only a little when i poke it. also it definitely wants to come off but i'm not

You : You have mentioned two of the warning signs of melanoma (change in size and two different colors). While i don't really have enough medical information to give you a diagnosis, considering that melanoma is one of the most deadly cancers, and the incidence has skyrocketed, the best and safest thing to do is see a dermatologist and have it biopsied as soon as possible.

This : This is difficult to tell without a clinical examination so i agree that you should have this evaluated by a dermatologist to rule out a skin cancer. Read more about moles and see some pictures of abnormal moles at the link below. I hope that helps!