Screen Shaking

Hello,

So a few months ago i cracked the screen on my laptop, it is a tiny crack in the upper corner of the laptop that separates that corner from the rest of the screen. But absolutely nothing went wrong and the computer works fine (just disclosing i have a crack if that may be the problem). Then about a week ago without anything to cause it i was just watching youtube and a thin horizontal line appeared across the screen its hard to see but the vid was white at the time it happened so i immediately noticed it. Right after it appeared the screen started shaking violently and the bottom of the screen was moved to just below that line and what used to be below that line is now below the bottom of the screen like it was pushed down and came back out the top idk if im describing this right but my eyes are hurting from the shaking so im gonna end here and i will check back to see if any of you guys have an answer. Thanks in advance.