Were you supposed to be more than 10% complete as of the status date? If you look at the Gantt chart - does the bar appear to be split - separated by dots?

If so, your option settings (Advanced) are likely moving the remaining parts of the work after the status date, creating the split in work. Do you have resources assigned to the tasks?

Also, it should not be necessary to press F9 to calculate the project. Ensure your calculate after each project (Options) is set to yes.