Stumped with what's wrong with DS. Measles, heat rash, alien encounter?

I'm not one to rush kids to the dr. for everything, and I'm pretty checked out on the normal illnesses my kids tend to get. However, this week DS (age 7) has me stumped. Every day he's had a different symptom. These include painful pressure in one ear, a low grade fever, red, irritated eyes, a painful itchy rash/hives on torso and neck (it's possible that was caused by the shirt having been washed in something he was sensitive to last year, this was his first time wearing it this year so I can't rule that out), stuffy nose, congested cough. All together those sound pretty bad, but here's the thing: he's had 1 symptom a day. By the next day that symptom is gone and a new one appears, and for the most part none of them have been even moderate (exception of the rash and ear pressure, those were disrupting). So it's seemed pretty obvious that his body may be trying to fight something off, and it seems like he's been doing a pretty good job of it so far. Today we were getting the kids ready for dance class, and DH noticed that now DS's torso is covered in a light bumpy rash AND he has a low to moderate fever. I'm guessing around 99-99.5 degrees, but his normal temp is low so about the equivilent of 100 would be my guess. Has anyone ever encountered anything like this before? So far he's not really "sick" enough to take him to the dr, and I'm not sure what I'd tell them or what they'd do anyway. Thoughts?