Don't stop nursing. Your daughter is receiving from your milk the specific antibodies that your body is creating right now for that specific virus. She's also getting all the many generalized immune protections your milk can provide. Beginning weaning at this point would only reduce her immune protection at a time when she's being exposed to an illness. She may develop a small respiratory infection herself but your antibodies are going to be there to save the day and she'll benefit from this new viral immunity that she's been able to develop while still under your milk's protective services. Any recommendation for you to stop nursing now would be very ignorant and I'd probably consider a new pediatrician although I know that good ones are very hard to find. If the advice is coming from your general practitioner, we'll have to forgive him or her as good breastfeeding education for doctors just doesn't exist. I expect pediatricians to educate themselves on this most important and basic portion of child health, while formula companies are dis-informing them daily.
Fever is your body's powerful means of killing bacteria and viruses. I wouldn't reduce it. Also, your fever reducing meds would be passed on to your infant through your milk. This is also not a reason to stop nursing, but Aspirin, Tylenol (acetaminophen), and Motrin (ibuprofen) have all been found to have very rare but serious consequences when mixed with certain viruses, such as the more commonly known Reyes Syndrome. These drugs are great for a headache or toothache but they're a little hard on a tiny liver and kidneys. When a child is ill, or may become so, it's not the best time to be challenging their body further with drugs. Your fever should help prevent your body from succumbing to a secondary antibiotic infection as well. This will prevent any need for antibiotics. If you happen to go on to these (I would not recommend it), be sure to give your daughter and yourself probiotic supplements during and after the antibiotic exposure. Studies suggest that your daughter would receive through your milk only about 1% of the dosage of antibiotic as you have. It's not a big concern (so still don't stop nursing) and probiotic supplements will counteract most any negative effects.