TMI

So I got the Nexplanon almost 3 weeks ago, I was supposed to start my period last Friday & I never did, I thought this birth control just wouldn't give me a period. Well I started bleeding REALLY bad at work yesterday so I went home & used the bathroom & see this in the toilet. I have been bleeding on & off since. I felt like I was pregnant, I just felt so weird but never took a test because I am on birth control & now I feel like shit. (I also have a 7 month old so I know my body so I know what pregnant feels like). I don't have insurance nor the extra money to go to the doctor & im worried sick & heartbroken.