I took my son on an overnight camp and woke up the next morning feeling fine. On the drive home, my neck started feeling a bit stiff, and I was getting a mild headache. By the time I was home (two hours) my wife had to rub my neck and shoulders because they were so tight and sore. My headache subsided with some Excedrin. Although the tightness in my neck and back never went away, the Excedrin helped me feel fairly normal for the rest of the day. That night, I started to get a burning sensation in my forearms. I told my wife it felt as if I'd just done an extreme workout and I was already sore from it. The next morning, I awoke to both of my hands swollen and tingling. My neck and lower back were stiff and I had a constant headache. I felt nauseous throughout the day. I thought I had kidney or liver problems or something like that. I never felt a bite or saw a mark because I wasn't looking for it. The next day I went to the doctor and got a bunch of blood tests. Once I got home, I noticed a bullseye-looking black circle with a white center. At that point I realized it could have been an insect bite. After ruling out Lyme disease, I am pretty confident it was a spider bite and the doctor agreed. I believe it was a brown recluse mostly because the symptoms seem to match up. My knees also hurt during this ordeal. It took about four days for major symptoms to go away, and about two weeks for the headaches and numbness (from time to time) to go away. I found that ibuprofen worked the best.