Toddler tooth decay

Patch • First they`re sour then they`re sweet.
Has anyone here dealt with toddler tooth decay? 😔 My 16 month old has a hole on the top of one of her front teeth,a bit on the backside & some discoloration developing on her other tooth. Also some little bleeding at the line of her gums. She doesn't get juice or a lot of sweets or anything so I assume it's from breastfeeding (kind of like bottle rot maybe?) & not brushing her teeth as often as I should because she was making it really difficult to do so there for awhile. What will the dentist do to help it? I plan on taking her asap so it doesn't continue to spread. I feel awful, like a really bad mom.Â