<human>: This is day 3, first it was a blood blister about the size of a couple grains of rice. By the end of day 1 it had swollen around the affected area in about the size of a quarter. Day 2, the blister is still purple, swelling continues but lessens a little bit. A white discharge (very little, like a pimple) came out of the blister, which is now recessed instead of raised. It's swollen so it is painful but I haven't had any other std-like symptoms, no burning, itching, no other marks, etc etc. 

I freaked out so i looked for a little bit into stds and didn't find anything that matched. It is on my dick, so be ready for that if you look at it. [This] album shows what it looked like at the end of day 2. You could see for a bit two distinct red spots when the swelling had gone down the most. Also, I pulled some kinda bug (didnt see it cause it scared the hell out of me) out of my undies while in bed not to long ago, but it wasn't the night before the swelling began. Any help? also, if this does look like something nasty, where should I go to get tested? any cheap/free places?

Condense the text into a few key points
<bot>: This looks like every other nasty spider bit I've had, but it's on my dick so I'm worried. Anyone want to help me identify it?