Might be worth changing your washing powder again, make sure it's a non bio.

The goats milk suggestion isn't as mad as it sounds, if you don't like that, try an unsweetened soya milk, and stay off dairy for a week. See if it makes a difference? Intollerances will make it flare up, and dairy is one of the more common.

As said, sun helps alot. It's trial and error with the creams. I found the skin repair cream by oilatum very good.
Eucerin was awful, made my skin sting. So personally wouldn't advise that one!

Good luck.