Macbook Air, Randomly Shutting Down

I have a problem, and anyone on here who is kind enough to help me out, THANK YOU.

okay so, i got a macbook air a year or too ago, but here is the funny part, on the way to a soccer game, i actually saw it on the shoulder of the highway i was on, stopped and picked it up. it was in decent shape. my dad works in IT and got a power cord, and reset everything so i could use it. It ran great. at first the camera didnt work, but then all of a sudden it came back on, its often rackety about things , but the last few months i havent had huge problems.

Now, any time i upload a picture to picnik, and after editing it try to save it, my screen goes grey, and it says i need to power it off..

is this because of it getting possibly dropped? or is it something else? i would really appreciate help on this. and even when i have alot of pages pulled up and im on facebook and things like that itll just tell me to shut it off.

any advice on how to fix this?
Thank You.

Please do not hi-jack someone else's thread. I've moved your post to a separate thread. Always maintain good forum etiquette and be sure to read our Sticky notes at the top of each forum before posting. Thanks for understanding.

I would open it up and see what it looks like in there. One thing to look for is the battery connections - unplug and replug those. Also, it is said that there are some color treated stickers on the mobo that turn color when exposed to water - so check that as well. Finally, give both power connectors a good scrub with a clean dry toothbrush to remove any fine dirt, grit, etc.