Router connects to My laptop without having to type in the passkey?

Ok, so i have a thomson TG580 router, And i recently clicked the wifi button thingy, (on the side) because i did not know what it did. But now everytime i connect to my laptop, I click on my routers ssid and it used to connect then, asked me for the passkey. But now it just connects without asking me to type in the passkey. I am worried it is Unsecured. But when i look at it, it says it has WEP secuirty, and thats good. But i just want to know WHY it connects to the laptop without asking for the passkey first, I understand it has secuirty, but i am afraid that by pressing the wifi button on the side of the router, caused it to be unsecure, and anybody can steal from it. I tried connecting it from my ps3, and it asks me for the WEP passkey, which is what its suppose to do. Sorry if you cant understand this very good, i was rushing. But any ideas or clues on why it does that? I dont have to cd anymore, it came with everything installed (passkey, ssid, etc.)