kernel panic?

so i was going about doing my thing on my MBP when the screen turned grey and a warning came up saying i had to restart my comp.

what happened? anything i should do to alleviate it? also, i've realized my mac has been acting rather sluggish when i have multiple programs open while it did not display this behavior before...can i do anything to help that out?

thanks in advance.

 

nope. no alterations to the system.

 

anyone have a idea?