You got a positive pregnancy test- false positives basically never happen (a few VERY rare instances of it happening can occur), so yes, you are pregnant. Have you made an appointment with a doctor yet? I'm sure this is very overwhelming, so let us know how we can help.
Congratulations on your pregnancy. I hope it is happy news. If not, we have a forum to discuss options. If so, this is a great forum to go through your pregnancy that always comes with lots of questions.
One thing that does lead to a false reading of a pregnancy test is not following instructions for when you read it. If you leave a test sit and read it after the instructed time, you will get a second line that is an evaporation line. Any chance that happened?
Otherwise, call your doctor and schedule an appointment. Mine does not see women until they are 8 to 9 weeks into the pregnancy but since you were on depo---- they will likely want to see you sooner. Let us know how it goes. hugs