Brown Recluse bites can be devastating even with timely treatment. One issue is that at first they look like a mosquito bite. Here is a timeline of the shots. be warned they get VERY disturbing (this is the time lapse of the picture sixpackshaker linked earlier):
Day1:
Day 3 - Could still be mistaken for a mosquito bite, maybe some poison ivy or something. A lot of people would just put neosporin on this:
Day 5 - Probably time to get to a doctor. But if its not a place you look at a lot....still you should probably catch this
Day 6 - Whoops, guess you waited too long....
Day 9 - good chance if you aren't dead then you will be soon...
We texans know about the brown recluse. It's a scary mother fucker. I had a friend get bitten by one, it almost killed him, and he only put off treatment for a day or two while he thought it was a mosquito bite.