Help asap

so here i am in the middle of modeling stuff when suddenly the view controls went inside out and back to front
my view is up side down and when i try to rotate it it has been inverted or something and pans at the same time
it is messing with my mind or something cos everything looks inside out

i have been working on this all day and everything was just coming together when this happened and i have only been using the auto up save witch is also stuffed up now so unless some one can help me it means i need to remake this witch will probably take another hole day


it was something in the tool shelf 3d nav thing