say i ping the server and get 300ms latency. Does this means when i play i should roughly get around 300ms latency also?

Because i tried to ping the frostmourne server and i got ~300ms, and when i actually logged in to WoW i got >1500ms :/

The weird thing is that in my apartment i have a friend living in the same block with me (just different floor) and i almost got no problem playing there (latency is mostly below 800ms).