Here's the dream:

My mother had left water in the bath. I hadn't noticed and stood in it. While standing in it I was not conscious that it was making a mess or had the potential to make a mess until I heard my mother yell out warning me but it was too late. A bit of water had overflowed onto unvarnished floor boards.

She was angry and pointed out the permanent damage that had been done. I felt it would probably dry and not cause any damage... it was only a tiny bit that had spilled.

She tried to hit me with a wooden spoon. I felt her anger and I felt fear and anger. I felt violent. I took hold of the wooden spoon so she couldn't hit me with it. I yelled at her and warned her if she hit me I would hurt her and I meant it. The yelling lasted a while.

If this dream feels especially significant, and I assume it must do or you wouldn't have posted it, it seems to go like this:

Because of something your mother either did or neglected to do, you have inadvertently/accidentally done something which may or may not be damaging.  At least, by your mother's standards (or your inner conscience's, since mothers teach right & wrong at an early age) it's very damaging and will have long-lasting effects.  You don't think it matters, really.

So - something you have done is against all your mother taught you (or is against your conscience).  You think it isn't important, really, but you know that she would not agree (you are trying to pretend it doesn't matter, but your conscience is not agreeing).

Part of you is saying that it's her fault you were in that position anyway - because of her neglecting to do something - teach you something?

Letting the water out - letting emotion out?  She bottled things up (didn't let the water out) and even though you spilled only a little you feel accused of doing something wrong?

I can only wonder - are you afraid to express yourself emotionally because your mother said "big boys don't cry"?  Or are you expressing yourself in anger, while knowing this is damaging those around you?

Otherwise, it could be something you have said - if your mother is a private person, and you have said something which "lets out" more than she would approve of.

My best guess - the prickings of conscience.  Is it a slippery slope, or does it not matter really?  Only you know what's been going on in your life.

Best wishes,
Tish