Chosen Solution
My HP Pavilion has a feature that dims the display when on battery power. I used the thing on battery for just a short time and went home and plugged it in. It normally brightens when plugged in but is staying dim. I am wondering if the battery must be 100% before it brightens up again.
thanks you guys! I went to battery settings and adjusted brightness..dont know how it changed itself..but its fixed..thanks to you all! its appreciated..have a great day!