it's a simple allergic reaction. either lubricant, something on your hands, or something on the inside surface of your clothing is surely the origin. change clothes, thoroughly clean your hands and body, throw away the new lotion (right after you take note of what's in it for future reference) and your wang will be normal in a matter of hours. i have experienced this a couple times, and the balloon effect of foreskin only is the key indicator.
There is something called phimosos, and it can be caused by infections.
Vance is right - you need to give the meds some time.
I can tell you that antibiotics can take a couple of days to work. With the discharge it could be something like gonorrhea or chlymida, the swelling I am not certain, it might be some kind of infection. Give the antiboitics a day or two and if it does not work I would encourage you to see another Dr.