Hi. When I started my laptop today (while plugged), the bottom right corner of the screen was dimmed. After a while the screen started to flicker as well. I tried restarting, nothing worked. Only when it was UNPLUGGED for a longer time, the dimmed corner disappeared. Then, when I plugged it again, to charge it, the darker corner appeared again and it started to disappear quickly after I unplugged it again. Now I can see just a bit dimmed dot at the bottom of the screen. What is it?