can’t login, blank pages, rss, and livepress issues

the login box will come up, standard, but when i submit my stuff it just goes to a blank page, so i can’t get to the admin panel/post/anything

i recently cleared my cache so my password and stuff had been stored and now i have to sign back in. before this though, i noticed that in the dashboard things would act weird too… I would update an option page or update something on any of those pages, and when it ‘refreshed’ it didn’t refresh correctly. it would have the ‘header’ stuff but the bottom panel (wherever i was) wouldn’t update

also, the rss feeds don’t work…
ex: https://www.mattmartz.com/feed/ it doesn’t look like it is echoing the xml data stuff

i haven’t modified either of these files so i don’t know what the problem is.

livepress works, but whenever i post something it won’t refresh the page like usual, it displays this plain text thing, i’m assuming what it posted to the livejournal site (can’t show an example because i can’t login…)

my site is at https://www.mattmartz.com