Lately my car's been giving me poor gas milage and felt a bit rough.
I've decided to change my spark plugs today and when I pulled
the old plugs, they looked pretty worn out.

I am no spark plug expert so I would like to ask you guys
how bad of condition these are in.

Here are the pics:

 

It's a little hard to see the electrode in the picts but they don't look bad to me. Why do you think they are shot?

 

they don't look to me but hard to tell. At 13,500 they should be good still shouldn't need to change them un til around 30,000

 

The plug electrode color looks good! That whitish-grey color usually indicates complete combustion without the imxture being too rich or lean. When you say "they looked pretty worn out", what do you mean??

You should be more concerned when one or two of the plugs shows a different color (ie. sooty black or extremely white). My guess is that you just spent some money on a replacement you didn't really need...

 

i already have 42k miles. so for sure i need a change? should i check one first or might aswell just do it?

 

They look pretty standard for the mileage. I changed mine at 40,000 miles and the fine electrode tips were worn right down almost to the tip of the center porcelain.

 

They look like standard textbook of a great running engine!
Thats how you want them to look, no oil complete combustion,
though I do agree for only 13,5 the electrodes could be in better shape.
I really wouldnt worry though.