How to solve "the connection was reset " while loading my website ?

I have developed a website(still under construction) named www.drissho.com . I hosted it 1 month ago , but everything was all right till yesterday. After adding a banner(120 kb) and some other changes everytime my website loads the firefox browser says

"The connection was reset

The connection to the server was reset while the page was loading.

The site could be temporarily unavailable or too busy. Try again in a few moments. If you are unable to load any pages, check your computer's network connection.

If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the Web."

I know a solution of cleaning cache of mozilla firefox , but it's work only once.the second time it display the same message again.

What should I do , Is it my browser problem or my coding or logical problem or banner image size(120kb) loading problem ... Please help.