Failed to connect/extreme lag for a certain time only

[Ellie]

The fact that it seems to be during a peak usage time.... and the fact that it is also un-peak time on the server suggests more that it is your connection.

Is anyone else in your house also using the connection, and potentially downloading?

It doesn't really matter much that your friend isn't lagging. Different cities = different phone exchanges. It could also be due to your hardware, eg, router.