Mirena coil and heavier periods

I am 15 years old I have been on countless contraceptives I have just come of the depo shot to go on the ius coil and it was a easy procedure there is a downside thought I have had cramps that only seem to be getting worse and the bleeding has gone from light to heavy this is the first day of having bad bleeding but I don't really know what to think I went to the doctors and the string were still in place and everything was fine and now the bleeding had become worse I have done all my research but I still don't know whether this is normal I have a constant fear of the ius being expelled or displaced and I am just really worried I know it has only been 1 month but I'll just have to see if it improves

I had the IUS Mirena fitted just over a week ago and it is the worst decision. I am now deeply regretting it. After being put on a waitlist for it due to painful periods, an appointment became available. I did some initial research through the NHS website and in the appointment, the Dr ran through a few things. The insertion was honestly awful. It took ages and hurt a lot. I came home in agony and felt the worst cramps of my life for the rest of the day. Since then I've had my period and it's again been the worst. Cramping, lower back pain, feeling like I need to urinate a lot, heavy pressure on my tummy and bladder. My period was also more painful than ever and I'm still bleeding. Fed up and now willing to wait months and months like so many women for it to possibly settle (but judging by most reviews and conversations with women who have it, it rarely works as the doctors say it will). They also put me on a 3-day course of antibiotics when I called to say what was happening. They think I have an infection but no one has cared to see me in person. Once the course is over, I am booking the first appointment to have it removed.

For me, having the Mirena inserted initially was very painful and I had bad cramping for several days after. I really liked not having to take a pill every day and my skin also improved. Unfortunately, I bled constantly for the 8 months I had the Mirena, and my cramps got worse while I was on it. It also caused pain during sex, so I ultimately had it removed.