One dose of depo, no period 7 months later. Pregnant?

Patient: I had one dose of the Depo-Provera shot on Sept. 9th of 2013. On January 3rd I got my period and it lasted for 8 days. Since then I have not had any spotting or a period. I took two pregnancy tests, the last one being around the 27th of February. They were both negative. I am a small woman, only weighing in at about 105 lbs. I have 2 children already, and both showed up positive on a test at around 6 weeks. Is it possible I am pregnant? Should I be worried that my period is missing? I have been on and off depo before, and my period always came back regular the month after the shot wore off.

Symptoms: Extremely bloated off and on
4lb weight gain
No period

Doctor: Thank you for your query.Further to going through your query, probably the chances of a pregnancy are remote, because the home pregnancy kits do not show a positive result. You also have taken the last test late after your expected menstrual cycle. May be it is a side effect of the depo injection you have taken. The side effects may not be the same everytime. It is advised that you consult a doctor and opt for a scan which will help know the reason for not getting your period.Hope that answers your query.Good day.