I just wanted to share my experience with this as I've had a very unhappy year with it and am feeling so much better now I've had it taken out.
I couldn't find all my symptons in one place when I searched for info but there are other people who've had the same/similar issues.
I didn't have any periods for the first 8 months which was great but then I started having spotting and eventually 6 weeks of bleeding which was stopped by a couple of months on the pill but started again when I stopped the pill.
But the main thing was the emotional side. I totally lost my sex drive. I could just about bear it every so often, but would've happily done without. This was really sad for me and probably quite hard on DH. I spent most of the time putting it down to DS being small and bf but within 2 weeks of having it out I feel totally differently and it's great! (Won't share too much info
)
I was also starting to suffer from anxiety, I think. When I had something that would usually give me nervous butterflies for an hour or so, I was starting to feel sick/dread in the pit of my stomach all day, and that was not like me at all.
I felt really vacant and struggled to follow conversations. Nothing heavy, just toddler's mum stuff but I felt like I couldn't concentrate. Same with the F1 (huge fans in this house!!) I just couldn't follow a race.
I was being a shouty old bag with the children. That's not unusual in itself
but was getting more frequent. I was being horrible to them every day 
I'm not totally slating it. I know it suits some people and wouldn't say don't have it. I know people react differently. I just wanted to put it on here so that if anyone searches and is feeling the same they will find someone who was in the same boat and now feels like a new woman!!
I was terrified to have it out in case the way I was feeling was just the new me after 2 children (I had it in when DC2 was about 6 months and still not sleeping!)
So anyway, sorry for the mammoth post, but hope this helps someone.