iPhone 4 Calendar Problem

[Iphonestumped]

I'm having trouble with the Calendar on my iPhone 4. Suddenly I can only see my calendar in a columnar format with times in left hand column, followed by a column with day/date header and a vertical list of the hours and events. I can't find a way to look at the calendar by month, select a day and see only a list of events for that day, like I could before. Any thoughts?