How do I get better faster?

I'm really stuffed up and I have a raspy sort of throat, it isn't sore anymore but it's still really dry and when I talk for a while I start coughing. I've been coughing up flem mostly yellow but some green, there was some very dark green. Now my neck is hurting on the left side and my upper back on the left side right bellow my neck. It hurts while I'm sitting and while I move certain ways. I can put it to my chest with only a little pull. Is this just the common cold? I've had it for three days and I was very tired and feeling sick for seven days before all of this came on, but I wasn't sick like I am now. What do I have? How can I make it go away?