Birth control

I recently got on nexplanon and became sexually active. This is my first period with it and it feels like somethings off. We had a pregnancy scare right when I got it but the test were negative. The bleeding is completely different. Even the color and it’s much thicker than usual. Is this a normal side effect for it to affect my period so drastically? Also my period is usually a lot heavier

Sorry if theses questions seem stupid TIA