In Game Lag

I do not know much about the Internet. But lately, I have experienced some awful lags. After I left Guild Wars on for 4 hours straight, when i returned to play, it started to lag. I could not see where I was going or what skills I was using. Most of the lag I experienced happened inside of Heroes' Ascent. Please tell me what has happened to my computer/internet connection. Thank You.

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Did you get D/Ced after this lag?

what is a D/Ced? This lag prevented me from playing HoH. Due to the connection, i could not play as an infuser or anything. But after I turn off my computer for about 7 hours or so and turn it on again the game won't lag unless i play for another 4 hours. ( Play 4 hours = game lag. Let computer rest for 7 hours = no lag. Play 4 hours after the restart = game lag)

Im getting lag in factions areas... which i really shouldnt be.

Also in underworld when you exit the labyrinth part and enter the ice place.. as the mo is training the smites we always tend to get loads of lag...resulting in the mo getting killed and me running...then getting killed irritating