Can't connect to the Internet!

I have a Dell and Windows Vista. I'm studying abroad and the wireless Internet has been working perfectly up until yesterday. I can connect on my phone, and everyone else can connect to the Internet, but I can't connect on my computer. So I think there's something wrong with my computer. I can connect to the wireless router, but not to the internet. When I diagnose the issue, it tells me to repair my wireless network adapter. When I try to repair that, it tells me there's still a problem. I know it's not the router, so I have no idea what else it could be. Please help! I have to access most of my text books online.