I had the mirena fitted nearly a month ago!! i am only 21 never had babies so having it fitted was painful!!
I experienced bleeding on the day of insertion but that was it and since then i have only had a couple of days of spotting. I am experiencing some slight tummy cramps at the min but thats becus i am due on this week so its period pain.
I had problems with the pill as i just bled for weeks at a time and i went for the coil because, the side effects are much less a risk than any other contraceptive, this is because the hormone is only released into your uterus, whereas with the pill, implant and injection more of the hormone can get into the blood stream. Also your fertility comes bk almost instantly when you have the coil removed. I have experienced no headaches, no spots, no weight gain no anything!! so so far its all good!!!