5 days sore throat, severe body/joint ache & fever (100-102). Thought it was strep or virus, but today I find a bullseye-like bite on my trunk. Can it be Lyme disease? Is it too early for blood test?

Epidemiology . When early lyme is suspected, the diagnosis is based on clinical grounds. Taking a picture of the rash & having a doctor examine it before it disappear is advisable. Other things can cause a bulls eye rash such as a fixed drug eruption, southern tick-associated rash illness, etc. Early recognition is very important. Its too early for an antibody blood test. Epidemiology will help your doc answer.
Is good thought. This is referred to as erythema chronicum migrans, and is an early sign of lyme infection. Blood tests may not be positive early on but please don't wait because of this. Go see your doctor asap and get treated with antibiotics because early treatment gives the best chance for cure.
See your doctor. Acute lyme disease can present with those symptoms and the rash like you described. You should see your physician for appropriate testing and medication.