been using the free version afeter i updated when i click checkout now it fails to load

So i was using the free version and i decided to take the plunge bought the paid version so i could use authorize.net -- i set all of that up but when i go to do a test i get page timeout server taking to long to respond after i add stuff to my cart and then click check out now. any ideas?

latest version of word-press
it was working before i upgrade to the paid version
i was thinking maybe because authorize.net requires SSL that because its on a test site that doesn't have ssl it might be why it wont get past that page i'm not sure though

edit* when i turn off authorize.net it seems to work fine so it has to have something to do with that i checked all of my credentials and everything just to be on the safe side still no go