I had my first Depo shot Nov 10th I had uprotected sex Dec 2nd - Dec 5th I should have started my period by the 5th of Dec and started to have light bleeding Dec 7th what could this mean. Could I be prenant it don't feel like a normal period no cramping just a little uncomfortable down there. I have been dizzy and more tired then normal. I it possible to be pregnant.

There is always the possibility that even while having protected sex and being on birth control, you can become pregnant.

However, when starting a new birth control, you are to expect irregularity within your period schedules.

You may completely miss your period this month, some miss multiple months in a row depending on birth control, and unfortunately,
Depending on each individuals body and how it's affected.

Don't worry too much, I would say just live life and see how it goes, if by the 1st of the year, you haven't had your period;
It wouldn't hurt to take a pregnancy test.