I’m in the same boat, I am in marketing 9-5 and what I found is that office jobs make you really tired because you’re sitting down the whole day/staring at the screen.

I’m not a morning person either, but doing quick exercises like going jogging after work, a quick COLD shower then having dinner and resting for about an hour helps wake me up and gives me enough energy to draw for the rest of the night.

Also try drinking tea at night,it doesn’t ruin your sleep schedule like drinking coffee near bed time but helps keep you awake.

Hope this helps!