Internet works on PC but not Mac??

Hi,

I own a white macbook (newest version) and everything was fine until, suddenly, I can no longer connect to my wifi internet at home after waking it from sleep mode. The internet works on two PCs at home (one desktop and one laptop) and airport goes from either "not connected" to "no IP address" to "Self-Assigned IP" (?)

I am not very tech savvy but have tried the following:
-restarting router
-restarting computer
-deleting/adding Airport
-firewall is off
-resetting PRAM

This sounds silly but I haven't been able to see if I can connect to a different network because I have to remain mainly at home for the time being.

I would appreciate any help! I've tried scouring the internet, to no avail. (Also, my apologies if this isn't the right section)

 

Unfortunately, I can't seem to get a connection using ethernet, either. Hm...

 

So I took my mac to the apple store, where the wifi there worked perfectly fine. They set up a new wifi location (other than automatic) for me to try and also a new account name. They also ran a system diagnostic test and everything came up fine.

However, back at home wifi continues to not work. I have no idea what to do!