I have been on the mirena for about 7 months now. My periods have become lighter and further apart (about 5-6 weeks). I started my period 3 days ago and it seemed normal at first, then turned so dark it s almost black and its thick like mucous and watery at the same time. What does this mean? Have I miscarried? I have also been taking hydrocodone 10/650 and amoxicillin for about three weeks but this wasn t listed in the side effects. Could that cause it?