Could I be pregnant ?

Chasity

I had a baby feb 9 2020, got a depo shot feb 11 I was supposed to get a 2nd shot may 11th but I never did and my period returned right back it was been really like/irregular.. my first normal period was last month on Aug 2 -4 lasted 3days that’s Normal for me but this month it didn’t come on the 2nd & still nothing yet . I took a test yesterday n it said negative so is it the old depo messing it up or could I be pregnant??