Yes I noticed something like that- I feel "foggy" the morning after my every other day 10mg of lipitor.Hard to quantify "foggy" probably very hard for an even older not very active person to quantify it. I just feel a bit "off"
My muscles-specifically quads- got sore after my usual ride
I have done EXACTLY the same ride-up and down the levee for 25 minutes- after 9 minutes riding there-9 minutes home-for 5 years.
No muscle soreness- knee soreness-yeah- I have gimpy knees- but no muscle soreness

So yeah-I do think statins cause significant side effects.Just go online-you will find many many people ascribing various side effects to them.
But their docs-see another side.They see ALL THOSE STUDIES showing people live longer and have fewer MIs