Wifi is incredibly slow on OS X El Capitan

So after installing OS X El Capitan my Wi-Fi is so so so so so slow.

My Internet Connection Speed is 2Mbps (240kb/sec) and it shows 2Mbps on my iPad and iPhone (using the speedtest.net app). On my MacBook Pro it shows me 120-250Kbps (10 to 25kb/sec) when I'm using Spotify, YouTube and anything that's Internet based (Apple Forums took me a minute to open)

I've never ever had this problem on Yosemite. My wifi works fine for sure. Even during downloading OS X El Capital from the App Store my speed was constant 230-240 Kb/sec but after installing El Capitan nothing works fine (Internet Based Applications)

I did everything I could. Deleted Wifi AP Name and added it back. Restarted everything (Router and Mac). Turned off Wifi and turned it back on.

I don't think its my wifi router or anything or else fault as my iPad and iPhone would have been affected as well.

Can someone please tell me if they face this issue as well and if yes what's the solution?