I entered in the Yngol barrow. After first step the lights are turned off. It's totally dark expect some blue shinings on the walls and sometimes after a few seconds you can see it blinked back to normal and then dark again. You can't use map, inventory or anything under tab or q and you can't activate anything you found in the barrow. You can open the system by esc but can't load the game. I have quit Skyrim a few times and reloaded the game and every time I enter in Yngol Barrow the problem appears again. Anyone having same troubles or knowing a way to solve it?

happening to me too, may be a glitch

This is a known bug. Since you are on the PC (or else your mention of tab and q are very odd) you can open the console and wait for 10-15 seconds, I saw on the uesp wiki that doing so might help. Worth a try, anyway.
Personally, I've never gotten ESC to work when this happens. Fortunately, this only happens to me when leaving Blackreach, which has like six exits, so I just try another exit.