Glad that I've worked about 2½ days on an angular component, with all the struggles, brainstorming and meticulous care for "good" and "readable" code, just to find out that I misunderstood the requirements. Had to completely rewrite it...

That’s a good learning moment for you, at least. Make sure you and the PO, are on the same page before you get started.

At least your project is agile and it was only 2 days. Back in the waterfall days I’ve seen weeks and sometimes months wasted.