I have a small, smooth, square red spot on my forehead. i notice it gets redder, but then goes back to a pink color. is it a mole or cancerous?

Likely hemangioma: Likely it is a small hemangioma- which is a benign tumor of the blood vessel. It can get redder if the circulation on that area increased- for instance after coughing, getting upset etc- and will go back to pink when blood flow gets back to normal again. However, nothing can substitute clinical examination- ask your primary care doctor to check it out. Does not sound like a mole.