It looks awful, Pia
I'd have the builder in - gut the bathroom and start again with a new suite and tiles. Lord knows why anyone puts any tiles or fittings in a bathroom that are not white. Then tackle the painting. Emulision comes off ceramics really easy. When I did my bathroom, I slapped the roller over the tiles too. Just wiped it off later with a cloth, for a neat finish. Ideally you want paint specifically designed for kitchens and bathrooms - more durable. A matt/satin finish would help hide the rough walls - all those dips and bumps.