I concur with crabs, big thing is a house centipede, crazy fast predator usually found in dark and damp conditions in most of the world. I've seen them in Canada, Florida and the biggest species I've ever seen was in Peru... thought it was small rat at first...
They often get stuck in sinks, tubs and light fixtures and can't crawl back out. They can drop they're legs when frightened and supposedly have a painful bite (not medically significant though).
I'd be really surprised if these things (or their relatives) aren't in Texas.