Yes, but fearing the HIV test isn't rational thinking. I guess it's possible that I may have been exposed sometime in my life because I didn't know the exact history of every woman I've been with, but I don't think it is likely ... and I've been fearing the test for 12+ years now.
Even if one was positive it would certainly make more sense to find out to start proper meds and no behave appropiately.
The test doesn't actually change your status, it just informs you of it. That being said, I'm still terrified of the test.