Yuck! What are these little worms?

[rubyslippers83]

I have been watering some of my house plants from the bottom (have had them sat in a bowl of water for about half an hour) and have noticed these worms in the water. Can anyone tell me what they are? One of them
looks like a small earth worm. Should they be there?! On closer inspection, there are loads of really tiny ones swimming about!

The resident Oligochaetologist say that earthworms would head up to the surface if the soil got wet. The pinkish one could be an earthworm - hard to tell with poor focus and so much soil. He suggests insect larvae.

The really tiny ones swimming about could be nematodes.

I get little dark pink worms that come out of the bottom of houseplants that I have potted in home made compost. No harm done over the past 5 years and they kick out really fine and nutritious soil from the base of the plant pot, I just add this (and the worms) back on top. I also think they help aerate the soil. They look similar to your picture 2, can't quite tell for the other pictures.