Maybe the sentence could be "Jeg ble kritisert mye"
Yes, that's another option.
Hva med "å ha satt"?
How about "jeg mottok"?
Nja... Motta usually means "receive", but as a I see "I received a lot of..." is allowed, I'm adding mottok as well:)
Why can't it be "mange kritikk"?
I think "mange" is used with countable nouns.
Mange biler, mange trær, mange barn
Mye penger, mye kaffe, mye tid.
And of course there are exceptions. For example I've heard people use both mange folk and mye folk.