For the "Eu fui assaltado" proposition.
"Three mean-looking guys stuck me up" = "... robbed me at gunpoint"
"... held me up" = "... robbed me at gunpoint"
An armed robber may use a weapon other than a gun to stick/hold his victims up. Back in '98 a couple of street kids leveled several glass shards at the underside of my chin to rob me of my wristwatch and R$30 cash. They ran off with my belongings. Then, in Feb. '99, I had to drive a couple of barefoot young men from one shopping mall to the other. They sat in the back seat but they had .38-caliber revolvers. And then again, in 2004, one single, tall young gentleman walked up to me at a street stop and demanded, "Me dá o celular!" out loud. I handed it to him.