Q: Wifi connection Mac Mini

suddenly I started to have problems with my wifi connection, iit started to be very slooowwwww ... Then I figured out that it was because I had to update the software that I did. and now I have OS X Yosemite Version 10.10.2 ... And it does nott connect. I have tried everything, reset the computer, reset the wifi connection,  reconfigure the network, and nothing seems to work...

WOrst of all ... My iPad is connecting perfectly...

ANy ideas?..