Computer Won't See Wifi Networks

So my laptop was working just fine until the day before yesterday. I didn't drop it, etc., but now it seems to be unable to see wireless networks.
Specifically, this morning I tried to connect it to a new network (I'm not at home) and at first it saw about 3 different networks (none of them in the house). Now, it doesn't recognize any networks at all. Is it possible that something is damaged on my wifi card?
My phone sees the network, which leads me to believe that maybe it is not a router channel problem, but something else. I have a 13 inch Macbook Pro from 2012 with Maverciks. Any ideas?


Thanks for your quick response!
I have actually rebooted everything and my computer now sees SOME wifi networks, but still not the one that is literally half a foot away from me. The one that it does see, it can't connect to...
I ran the Diagnostics report, but that seems pretty useless...