I am seventeen and just had the mirena put in on March 4th. I have been spotting non-stop (which is brown and thick). But I, finally, just had sex with my boyfriend on Friday and afterwards I started bleeding, not like the brown thick stuff, but like i was on my period. I don't know if this is normal, and all day today, I have been having terrible cramps. My abdomen is sore and crampy and I'm very concerned about this. I dont know if this is a serious problem or if bleeding after sex with the mirena is a normal thing?