Thanks for your question on Health Care Magic.
I can understand your concern.
By your history and description, possibility of
skin infection in nipple area is more.
You are having swelling and discharge on pressing, these suggest
abscess formation and oozing is mostly pus.
So you need to get done surgical dressing if that abscess.
You need surgical dressing, antibiotics and anti inflammatory drugs.
Wear cotton undergarments only. Avoid moisture and keep proper hygiene of nipples.
Don't worry, you will be alright. You have not done anything wrong, but get done surgical opinion and dressing.
Hope I have solved your query.
Wish you good health. Thanks.