Have a red welt of breast that is warm to touch?

This area of skin has been red and warm to touch for about 2 weeks now, from day to day it gets bigger then smaller, from 1 inch to around 3 inches. Today it has some dry patches. I am very pale skin so it is a light red and not noticeable by camera so it is hard to take a picture. I am scheduling a appointment with my doctor for tomorrow, do you think I am jumping to conclusions thinking it might be something bad?