Hi I have ipod/ipad/samsung galaxy phone and windows 7 pc, I have wifi on all these devices but hve trouble using Facebook and all of the divices. Both of the phones can connect when using the 3 or 4g network with wifi disabled but will randomly log into facebook. My computer is similar it logged on this morning but then when i clicked a link WITHIN facebook the page it says unable to load page. My daughter ipod 5 does the same but also youtube wont open either. I am pretty sure it is a wifi issue but DIDNT want to buy a new router for no reason. Any help much appreiciated.

JonaMost likely your equipment is good.
Who is the provider for you internet service? (ISP)
Recently some providers have had bad service for unspecified reasons.
It varies by region.
SOMETIMES the 3G and 4G serve is better, even in the same area.
The best I can offer is that you contact the ISP you are using.
I have had Internet services for four different providers over the past 13 years at this location.  This last year I have had more problems than EVER. The prov ider does  NOT inanimate with me  what the issue is.
There has been much speculation, but no clear answers. But there is a lot of anecdotal stories to support the idea that the ISP companies have a problem.
Here is one of many:
http://www.extremetech.com/computing/177073-why-netflix-streaming-is-getting-slower-and-probably-wont-get-better-any-time-soon
Quote

...Netflix and Comcast have come to an agreement. Netflix now has a direct CONNECTION to Comcast’s network (peering), and Comcast users should see much improved service as a result. Money changed hands, but no exact figures were made public.