I Have Lyme Disease, Was Bitten By A Tick On

I have Lyme disease, was bitten by a tick on the 26th of July 2015, tests come up negative for Lyme, but I'm getting all the symptoms. My doctor put me on Doxymycine for 10 days and I begged her for more antibiotics since that seems to be in all the info I read about Lyme to get on antibiotics for 4-8 weeks. She did extend it now with apo-cefuroxime250mg for 21 days and I was just given some expired claritromycin 500mg, which is also used to treat Lyme. Do you think it's safe to take it after my round of cefuroxime is done?