Hello Poppy, sorry for taking so long, I've been out all day, just got back in.
Your username is showing as active so you should be fine to log-in. Have you cleared your cookies and temporary internet files lately? This is most likely the problem now.
Some other questions, have you changed the security settings in IE lately, have you changed your site password?
Let me know how you get on, if you have no luck then I'll try and delve deeper.