It is possible that Mirena may not have been properly placed so your doctor should examine you (with ultrasound
as well). It can be symptoms of pelvic inflammatory disease
. I think that you have a predisposition to such complication or even had had chronic pelvic infection
which was not treated properly. So I consider that in your case oral contraceptive pills
with low hormonal
concentration or locally acting contraceptives (they destroy the sperm cell inside the vagina) would be more preferable and you can also use female condoms. Probability of weight gain is not very high but exists. Please go to your gynecologist as soon as possible.
Wish you Good Health
Dr O. Aleksandrov