Some people will not develop a rash. Lesions fade after about a month without treatment. With antibiotic treatment lesions resolve after several days. Round, red lesions occurring hours after tick bite are secondary to hypersensitivity reaction and should not be confused with the rash of Lyme disease. Later stages of Lyme disease involve a secondary rash and nearly constant fatigue.
Fever is also common.
Muscle and joint aches may mimic a viral illness. These later symptoms are intermittent and rapidly change. Neurologic and cardiac symptoms can also occur in later disease. There aren't any reliable tests that definitively diagnose early Lyme disease. Your health care provider will rely on your symptoms and history and maybe some lab tests to make the diagnosis.