hard red lump that has become itchy and sore.. Please Help!

About two weeks ago, a pea sized red bump with a white spot in the middle popped up at the lower end of my shaft. I did research, watched it a couple days to see if it changed. About a week ago, I read this one article talking about the difference of std and sebaceous cysts. The article stated that cysts usually disappear with the application of warm water + steroid cream. Did this for about two days, and it deflated a moment after (like it said it would) - so I continued applying cream, and only applied hot water - 2 more days (I believe) and happily waited for it to disappear. Here it is, one week later. And the same bump is the same as it began, if not worse. The white spot is gone and there is more yellowish color, occupying most of the middle. It has continued to get more sore/itchy than it ever was and seems harder than it was, and will move together, if I lift up under it (however I wouldnt really touch it too much before, because I was scared of spreading it). I have recently started applying warm water again, but have not seen any improvements. I will set up a doctors appointment next week, if it doesnt go away, but that is too much time for my mind to jump to horrible conclusions. I would also like to add, previous to this bump, all of my std tests came back negative, however I did have unprotected sex with the same partner, who had just recently been with one other guy I am already full of self-pity and understand how stupid it was; I am now concerned with simply taking a leak now - due to my fear of self-contaminating myself in a new place.Also, how likely is it that someone will self-contaminate themselves? Is there any home remedies to help this heal? How quickly does it take for an infection to arise after being exposed? Would it be a bad idea to try to remove it myself with a sterile needle? And finally, can anyone ID what this bump is?Thank you for your time and your attempts to diagnose me. Here's a picture.. if you dare. 

http://www.keepandshare.com/userpics/m/u/y/l/oco3737/2013-06/ss/messagepart-91656172.jpg?ts=1371624750