1st;

Is your dipstick normally accurate? How do you know the oill pan is full? Unless there were changes, I find it odd where you can say your dipstick isn't reading anything yet you have oil.

Second, do you see where it is leaking from? A lot of times, if a front or rear main seal gets bad enough, it can twist itself into a bind and walk out of its seat. This cause you to loose oil very rapidly.

Unless you've changed something, I seriously doubt you have sufficient oil. Try filling it back up and check the oil as you do. Then look for where its leaking from.