Well kinda, but not in the way that you think. What a web browser does is when you browse to a website, it save the resources that makes up menus, tool bars, etc (commonly used elements on a webpage) on your computer so the website doesnt have to load everything, everytime, which speeds up page loading time. you just deleted those files. You didnt break anything. The browser just had to reload Twitter in whole again instead of just using the local stuff.
Sometimes when websites are under large loads, it can hiccup and mess up sending all the pretty pictures, so you end up with what you saw. refresh the page or delete the data again.
Hope that made sense.