They are some kind of worm yes..are they dead at the bottom of the pool? This is very common. I frequently have brown, pink and white worms at he bottom when I take off the winter cover. Saw some tonight. I was actually looking for answers myself.
There small parasites called worms I had them not long ago the best thing to do is tell someone at the chemist that you think you have worms and they will give you some tablets (they taste lush) you take 1 every 2 weeks while you have worms keep your hygein up have a shower/bath everynight and after youv'e been to the toilet wash your hands thourally oh and never forget to clean under your nails because thats how the cycle repetes of the worms you can get worms by too much sugar in your diet or un cooked meat I hope this helped and I hope you get better soon!