OMG I HAD THE SAME THING HAPPEN TO ME NOT THAT LONG AGO!!!!!! i just had to suck it up and keep living in my room. i just stayed away from where i had seen it and one giorno while is was at school my mom found it and put it in the garden.
so my advice? either: 1.wait-it'll mostra up eventually 2.run away to antarctica 3.get bitten and pray that it's a radioactive ragno so te get spidey powers!
If it's brown and small then te better go into another room because those are the most poisonous. It's called a Brown Recluse and if it bites te te will start to see your flesh open and te can see your insides. And I'm not kidding. Look it up. If I were you, I'd sposta out.