I have a close family member who is a (very good) childminder and my daughter also attends one.
If she's given you notice and is keeping the other children, it's down to numbers, behaviour or a clash of parenting style. Some CMS swap older children out for younger, due to the funding (they get paid more for younger children by the local authority) but that usually happens around age 3. It's more likely to be that something is making her day harder, or throwing off the balance of the wider group.
If she hasn't told you, you're very unlikely to find out now, so it's best to just let it go. It sounds like you have a complete clash of communication styles anyway, so it's probably for the best.
For what it's worth, it's the bare minimum for CMS to give an update on progress, naps, activities, toileting, feeding etc. - even if it's just a quick chat on collection. It's pretty poor if she's not doing that.
The presents are a really nice idea - again, I think it's the minimum to give a gift at Christmas, end of year etc. to the people who look after our children. It's common courtesy to say thank you for a gift, so understandable to be upset if she ignores it.
She was likely rushed off her feet in the morning, with other children to keep an eye on too. As people have said, she still had a full day to complete - if you'd been picking up you may have gotten a proper 'goodbye'.