Confused Parent Struggles with Screen Time Rules...

So I've been this over-the-top parent who's super strict about screen time for the kids. Like, two hours tops a day... But here's the thing... yesterday was so chaotic, and I'm just feeling overwhelmed all the time lately. So I let them binge-watch their favorite cartoons all afternoon while I tried to catch up on some emails... It felt like such a relief at the moment but now I feel terrible. Am I really doing this much damage by being lenient once in a while? Any advice would be great...