One problem solved, another starts

Ok, i solved the firewall problem from earlier. Except now i have an internet issues. Ok we have about 4 or 5 computers on our small network at home. Yesterday, the computer was running slow so i restarted it, when i did i was connected to the wireless but not the internet. But now, it says i'm connected to the wireless but i cant get on the internet, when i run diagnostics it tells me to check the router, but the other computers on our small network can. Does anyone know how i can fix this?