Skin Cancer Forum - Unsual Growth, Please Review My Symptoms

I am 31 years old. I am half irish and half puerto rican. I have a dark complexion so I never worried too much about skin cancer. I had alot of sun exposure up to the age of 20 but have had very little sun exposure since then. But then I got this growth. I have had this growth for quite a while. I would say about 3 years. It started very small, like a skin tag and grew very, very slowly. I didn't even pay attention to it till it had been growing for a year or so. Back then it was half the size of a pencil eraser or smaller, flesh colored to pink, no pain, no bleeding, no crust, no redness and perfectly circular. I didn't worry too much about it cause I had always read that the mole had to have irregular edges and be dark brown to black but now I realize that is just for melanomas, not squamous or basal. Then it grew some more to the size it is now about the size of a pencil eraser now. It has stayed this size for quite some time. At this stage, the color turned more pinkish/red and developed a dark ring around the nodule. It stayed like this for a long time. But still no pain, no bleeding, no crusting, no getting bigger.... But now, as of 3 days ago it has been changing rapidly! And it's freaking me out. Now it is dark red to purple, it has developed this white, crusty top layer, it is very swollen and tender and painful and the dark ring around the nodule that was there before has now changed to a bright red color and grown to the size of a half dollar around the nodule and this area is raised and swollen and it looks like the nodule got a little bigger. The red ring around the nodule spread to the size of a half dollar in just days!! And the pain won't let me forget that it's there. It is sunday so I have to wait till tomorrow to make an appointment but I am beside myself with worry and need some kind of insight into what this may be so that my anxiety can be momentarily diminished. Is this squamous cell carcoma? I have looked at some pics of squamous and it kind of looks like the pics but not exactly...Thanks!