You are doing the right thing by staying on top of this. If you have a fever and your breasts are extremely sore, then this should be treated like an emergency. You want to address it right away so that you can continue to breastfeed. You doctor may recommend antibiotics. Here are some other suggestions.
Expressing your milk to keep it flowing can help to clear up any blocked ducts and prevent a possible infection from spreading. Even though it hurts, breastfeeding or at least expressing your milk in a hot hot shower can help. Sometimes the bacteria in your baby's mouth can begin to infect the breast tissue. And dryness can lead to cracking which can introduce infection.
Some suggestions include getting a finger cot for your baby and gently brushing your baby's mouth and tongue. Then, try rubbing some coconut oil onto your breasts to prevent cracking. Coconut oil also promotes the growth of good bacteria and inhibits some strains of bad bacteria. You will also want to steer clear of eating too many carbs and avoid sugar and alcohol entirely.
The most important thing to do (going forward) is to wash your breasts before and after breastfeeding. It is important not to use antibacterial liquid soaps, because they can be too harsh and often have perfumes and other chemicals that are not safe for your baby. The best way to wash your breasts is to wash using a gentle perfume-free bar soap and/or to take what I call a hygiene bath and soak your breasts.
A hygiene bath is just a warm bath with a few tablespoons of iodine (the dark purple iodine solution that you can buy at any drug store) and a cup of salt (regular salt, iodized, or sea salt all work fine). Together, the diluted iodine and salt bath water inhibit infections. You can also do the same thing in your sink... just with a little less salt... and just "dip" your breasts into the sink.
[Edited my moderator to remove promotional content]