17 and I have an IUS

I've just started my fifth week with an IUS and this happens to be the 23 day of my period. 
Since having the IUS fitted, I've been bruising, in a lot of pain, an emotional wreck and bleeding... It's be such a pain to have and I honestly regret it. This won't be the same for everyone but personally I feel like this was the wrong form of contraception for me...