iCal multiple duplicates of events created for one

Please help. I created AN event in iCal for my work calendar. Repeats M-F, 0730-1600 thru March 2014. I've changed the "hours" of some of the "events" as needed (for example, vacation time, other time-off, etc.) Instead of ONE event, each DAY is showing more than 100 views of the same event. Viewing the calendar is especially useless on my iPhone 4S - it's solid green (work cal), takes forever to load and, as I mentioned, useless. I'd delete the entire calendar, but I have to be careful not to delete "views" that may show the amended work hours. Please, offer some hope ... and HELP!

Bill