I think I have cockroaches?

About a week ago i was in the shower and saw a shadow of a bug on the shower curtain. turns out it was a cockroach. ive been looking up pictures of the different kinds and i believe it's an oriental. its brown and the wings are shiny. i also noticed some sort of bug on the kitchen floor that i have never seen before. the only way i can describe it is that the body looks like a spider and the top part resembles a crab. could these be baby roaches? it's freaking me out because i found another one of these bugs in my kittens' litter box. i also found a roach in the litter box a few days ago. we got the kittens about a week ago, when i first discovered the roaches. is there any way the kittens we got could have carried baby roaches into my house on them? we got the kittens from a dirty house and we're trying to rid them of fleas. our house however is very clean which is why i'm so frustrated with this recent bug problem. i know roaches do not need a dirty place in order to live. also, last winter i found the same kind of roach crawling on my kitchen wall. after we killed it, we did not see anymore until this time around. any information is helpful, thank you.