The initial symptoms of Lyme are a 'flu like' reaction - so those symptoms are not at all uncommon for these infections. Regular doctors have a hard time diagnosing Lyme when there's a bulls eye rash present, so I wouldn't count on their expertise for less definitive symptoms.
And yes, at 5 weeks post bite, it's possible that it's too early for antibodies to have formed for a positive test.
Herb only treatment for Lyme & Bart ended 12/11 - no active symptoms for 2 yrs -Herb only treatment for Babesia ended 12/12www.healingwell.com/community/default.aspx?f=30&m=2977364
Had Lyme, Bart, Babs, RMSF, Ehrlichia, Myco, Anaplasmosis, EBV
New Lyme case 8/2014 - Healed 1/31/15 - unknowingly had Asymptomatic Babs and Asymptomatic Bart, being treated now though (2/2016)