car shaking after spark plug change.

So my car was popping a p0300.

I did fuel injectors, ran car sounded a little better. I bought new spark plugs and the ignition coils.

I put anti seize or whatever on the threads of each spark plug. I put the electrode gel that came with ignition coils, inside the little boot thing the instructions told me to.. I put them in, tightened putting everything back. Now my car shakes heavy. When I started car my seat was moving. It was shaking rough enough for me to turn car off because its never done that before. Now, it didn't do thst before I changed spark plugs. Changed them and boom. So wondering what I did to spark plugs that would make this happen?

Lemme know thank you !