Hi tpup, welcome to the board!
What dose of Ceftin are you taking? Twenty-one days is not long enough treatment especially if you have been infected for three months. It is my understanding that six weeks of the proper dose antibiotic is the minimum treatment time for an infection caught within two weeks of the bite. A longer infection needs longer treatment. Please do whatever is necessary to ensure you get proper treatment as soon as possible. Early infections are the easiest to cure.
Below is a Lyme symptom list. You can have any combination of symptoms.
It is very important to see a knowledgeable doctor. Many doctors do not understand Lyme and treat with outdated protocols. Besides Lyme, ticks can also transmit several co-infections including Babesiosis, two types of Ehrlichiosis (HME & HGE), Bartonella, and Mycoplasma. Many people who have Lyme are co-infected. It may affect treatment choice and progress. It is important to be tested for these by a Lyme reputable lab such as IgeneX in Palo Alto, CA. Have you been tested for these?
If you need a doctor recommendation, you can email me at firstname.lastname@example.org
Exercising when possible is very beneficial for Lyme. It oxygenates the body and increases body temperature which are two things detrimental to the Lyme bacteria. It is also important to eat healthy, get enough rest, detox, and take appropriate supplements including high-quality acidophilus. They replace the good bacteria and help prevent yeast overgrowth. The best ones to get are refrigerated and have a high culture count. Most health food stores have them. Wait at least two hours between taking the antibiotics and acidiphilus.
It is also important to learn as much as possible. I recommend reading Dr. Joseph Burrascano's 2008 Diagnostic Hints and Treatment Guidelines For Lyme and Other Tick Borne lllnesses at http://www.ilads.org/lyme_disease/B_guidelines_12_17_08.pdf He is one of the top Lyme doctors in the country, and many Lyme doctors follow his protocols. He discusses antibiotics and doses starting on page 18. I also recommend the books "Everything You Need To Know about Lyme Disease Second Edition" by Karen Vanderhoof-Forschner and "The Lyme Disease Solution" by Kenneth B. Singleton M.D.
Good luck with your treatment.