Still no period, could I be pregnant?

I’ve been on the depo shot, but recently stopped (been off for 8 months, been out of my system for 5) I bled 2 days last month (17th and 18th) then this month didn’t do anything. But had pink discharge on the 20th. I went to my family dr about a high heart rate and we was talking about this. She thinks that when I bled on the 17th and 18th that would of ben my period and I missed it this month... I take urine pregnancy test but comes back negative.. could it be because my hormones were messed up from the depo and still be pregnant??

Thinking about getting the pregnancy test through blood test just to be sure but want some opinions in the mean time.