Bleeding after sex... recently inserted Mirena.

so almost 3 weeks ago I had the mirena inserted, I got my period a week later and had some spotting afterwards, however it had stopped in the last couple days. I had sex without a condom for the first time last night, and now I am experiencing bleeding. is this from the mirena? am I pregnant? Is this something I should worry about? has anyone ever experienced bleeding after sex using mirena, or is this just regular bleeding while my body adjusts? I’m also having cramps.