Mastitis after weaning??

It’s been over a week since I weaning my 18 month old and I started to feel a hard knot underneath my breast. It was very painful so I assumed it was a clogged duct since I stopped cold turkey. This is day 4 and I started to notice the redness last night. No fever or flu symptoms and the pain has actually gotten some better but it’s becoming more red. Has anybody experienced this before?