I left work on time and still got asked “why I’m already leaving because there is so much work to do”

I worked from 9:00 to 18:00 with an houre lunch break in-between. I worked my legally 8 hourse so I decided to leave at 18:15 (!) because I was exhausted and tired. After I started to pack my things, my team leader asked me what I'm doing because there is still work to do (nothing what can't be done by tomorrow); I just said, that I'm leaving. Although the team leader held an moral preach I just said thats already past 18:00 and that I'm leaving now. And so I left. I'm curious about tomorrow and what my colleagues (and team leader) will say.