Can't turn Kobo Glo on again, can you help me?

Ok, last week I used it to read some books and, as usual, turned it off as I'd finished. This week, I've tried uncontable times to turn it on again but it wouldn't work.

I've tried connecting it to my computer (because it usually helps when it freezes), but It hasn't come back to life yet. I've tried charging it (even though I'm almost sure it is charged enough to turn on), but it didn't work.

The funny thing is that it's not completely dead (at least I think so), because it still shows that "kobo livraria cultura" on screen. Any help or tip?

And yes, I've tried that little hidden button for reseting, and pushing the turn-on button at the same time I press the light button for a few seconds. I'm quite desperate. :/