What Causes Delayed Periods After Using Medroxyprogesterone?

Hello, My OBGYN prescribed me Medroxyprogesterone 10ml for 10 days to shorten my periods. I have just firnished my 1st series. I would normally have gotten my period 2 days ago because my cycle was every 24 days before taking this pill. Now I don't know what to expect. I felt all of the PMS symptoms over the weekend, am I still going to have a period? or am I going to skipp it all together. I know he said it was going to shorten my period, but he didnt say anything about skipping it. I'm just wondering if my cycled is going to change.