Battery got to zero for the first time kinda nervy

I have had a 256gb lcd since november and i love it a lot and don’t play it for longer than 2-3 hours. I cap the battery at 90%.

About a week ago I was playing and I put it to sleep to watch a movie and forgot and then got busy with work and uni and sat down to play and it’s been on zero probably for a week. Is letting it be on zero for this long bad for the battery life??? I like to take care of my things as Im not super tech savvy.