Unless you like..fucked a sammich and then gave it to them for THEM to fuck, I don't think you did anything. And if you DID do that...Well, I think you have more issues than this forum can help with.
This is from JackinWorld.com:
"This is very common — more than you think. It's especially common for guys who are going through puberty. You've probably heard that puberty changes your body chemistry, causing you to sweat more, right? These bumps have to do with sweat glands, and they're entirely normal. Other bumps are the follicles of hair that has not yet appeared, and still others are acne, just like the pimples you get on your face. In all cases, there's nothing you can do about them. However, if you are sexually active and have bumps on your penis that resemble little clusters of grapes, there's a chance it could be condyloma accumulata (venereal warts). Though relatively harmless, venereal warts are viral and contagious and you should have them checked by a doctor.
If you're worrying about how someone might react when they see your penis in an intimate situation, relax — they have their own insecurities about their bodies and are probably thinking very similar things. As you get older you'll learn that everyone's body has imperfections, and when people get close they learn to look past that. If they don't they're probably too young to be having sex anyway."
If you're a pretty late bloomer into puberty, as you ARE only 19, you may still be getting blocked hair follicles and possible zits on your peen0r. I got one once. It hurt like hell to the touch, but eventually went away. It looked sort of like the one on yours, actually. But, as others have said, I wouldn't squeeze it if you don't know what it is. Popping some random unknown growth on your body wouldn't be good...
I'd say give it about a week. There's a chance that, with the stuff on the condom, something may have gotten into a pore and clogged it. If it doesn't look like it's changing or if it spreads, go see a doctor.