You’re right - they really are tiny things! And yes, that rydw i stuff is ‘standard’ Welsh, but everyone will understand you whichever you use. Don’t sweat the small stuff, as they say. In fact, don’t even sweat the big stuff, it’ll all hang together in the end.
Welcome to the forum, SSiW, and the amazing new life that awaits you in the world of Welsh! (There’s a portal, and magical beings, and dragons and everything...)