Game is broken

The game is broken as fuck... I have a screenshot of my death recap... saying that two people (panth + kat) Did 2045 dmg to me in 2.95 seconds.. When I tally up the damage it's only 15XX dmg... Been noticing a lot of bullshit with the game too.. like certain champs will take inherently less dmg regardless of their armor/magic resist and it will be champs that don't have any dmg reduction. I.E Gangplank will take more damage than Jayce even though they have the same amount of armor/magic resist and same life. I've been in situations where I had more life more armor and more magic resist than an enemy tank and I'd get blown up in two seconds and theirs would barely get scratched.. (we had fairly even dmg to tank ratio on both teams) It can't be only my copy of this game that acts this way... nor can I be the only one noticing this...