Hi glamourgirl, welcome to the Lyme board!
I think your doctor is smart for wanting you to get tested for Lyme. So many doctors are ignorant about this disease. From what I understand, LDN helps the immune system function better, and it sounds like you have experienced symptoms since starting it. I am not a medical professional, but I think it is possible that your symptoms could be a result of your immune system fighting something since it is working more efficiently. LDN is sometimes prescribed for Lyme patients.
Below is a Lyme symptom list. You can have any combination of symptoms.
Tickls can also transmit several co-infections. No Lyme test is completely reliable, and results can vary by lab. It is my understanding the ELISA or titer is the least reliable test and the one most doctors run first. The Western Blot is a better test, but it should be done at a Lyme reputable lab such as IgeneX in Palo Alto, CA. You can call them at 800-832-3200 and ask them to send you a testing kit. You can also ask about the price. You take the kit to a doctor who is willing to draw the blood and send it back. The results will be reported to the doctor.
The Western Blot lists a series of numerical bands with a + - or IND rating after each one. Although the CDC requires several bands to be present for the test to be positive, many people who have Lyme do not have this many bands. Lyme doctors focus on which bands are positive--some are specific for Lyme. Labs such as Quest and LabCorp do not list all the Lyme specific bands that IgeneX lists.
While it is possible you may be having side effects from the med, I think it is a good idea to at least have the Western Blot test done.