Sternum cracking / poping and getting worse.

So over the past few months or so, I've noticed my chest has been cracking. Like when you crack your knuckles or your neck or whatever. But at first it only happened in the mornings when I'd wake up and stretch. But now it's worse. If I even move it cracks and makes noises. It's mostly in the middle of my ribs, on the sternum / partial right side ribs. One of the ribs feels slightly elevated, but that might just be my mind playing tricks on me? Other than that I've gotten sick. My chest feels at a colder tempreture than usual and my chest seems to ache in general. It's not to severe, very withstandable. But I'm worried, and frankly have no clue what it is or what's going on. Any idea's?