|Unless your router is failing or has temporarily "lost it's marbles" then the router will be the same 'speed' it's always been.|
Try recycling the power on the router. Unplug it, count to ten slowly then plug it back in. Once it's finished booting, see if it still seems slow. If it doesn't then this is all you need to do should it get slow again.
If the frequency with which it "loses it's marbles" (that's what I call it when they act weird but behave properly after recycling the power) increases, the unit is probably dieing and should be replaced.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.