Engine/Tranny bucking

So my tranny has been bucking and jerking while im driving. It will hold gear for a while and when i goes to switch gears it takes an unusually long time. And the engine feels rough too and is jerking while driving. And today it was bucking hard at idle and it almost died on me while sitting at idle. I don’t know if it’s still bad gas because i had that problem last week or something worse. Any help will be greatly appreciated.