EWW, never ever go to google to find information:
It is estimated that 80% of reported brown recluse bites may be misdiagnosed. The misdiagnosis of a wound as a brown recluse bite could delay proper treatment of serious diseases.[3] There is now a ELISA-based test for brown recluse venom that can determine if a wound is a brown recluse bite, although it is not commercially available and not in routine use.[24][3]
There are numerous documented infectious and noninfectious conditions (including pyoderma gangrenosum, bacterial infections by Staphylococcus and Streptococcus, herpes, diabetic ulcer, fungal infections, chemical burns, toxicodendron dermatitis, squamous cell carcinoma, localized vasculitis, syphilis, toxic epidermal necrolysis, sporotrichosis, and Lyme disease) that produce wounds that have been initially misdiagnosed as recluse bites by medical professionals; many of these conditions are far more common and more likely to be the source of mysterious necrotic wounds, even in areas where recluses actually occur.[3]
Reported cases of bites occur primarily in Arkansas, Texas, Kansas, Missouri, Colorado, and Oklahoma. There have been many reports of brown recluse bites in California (and elsewhere outside the range of the brown recluse); however the brown recluse is not found in California[25] (though a few related species may be found there, none of which has been shown to bite humans). To date, the reports of bites from areas outside of the spider's native range have been either unverified, or - if verified - specimens moved by travelers or commerce. Gertsch and Ennik (1983) report that occasional spiders have been intercepted in various locations where they have no known established populations; Arizona, California, Colorado, Florida, Maine, Minnesota, New Jersey, Mexico, New York, North Carolina, Wyoming and Tamaulipas (Mexico),[26] which indicates that these spiders may indeed be transported fairly easily, though the lack of established populations well outside the natural range also indicates that such movement does not lead to colonization of new areas.
Make sure you tell us what the doctor says.