Ahhhh!!!! It's making me crazy. Cannot add new posts or pages. WP freezes up.

I really need help on this fast! I cannot add any new content at all. The dashboard freezes up completely. I disabled all plugins – that didn’t work. I went back to default theme- that didn’t work. What is happening? I have to add pages and posts….this is a blog. I posted earlier, but haven’t heard anything yet (and you guys know me). I feel really frustrated b/c I’ve not been able to work on this for a few days and now that I can, my dashboard is broken. Please help me wpmudev buddies.