Has anyone experienced weight gain with the Mirena IUD?

so a little background: I'm a 5'9" female and I've had the mirena in for about three weeks now. lately I've been really careful about what I eat, and the person that installed my Mirena IUD informed me about the possible side effects, none of which were weight gain. The last time I weighed myself on the scale I was 128, and I just weighed myself recently after over a month. apparently now I weigh 134 lbs, and I'm really disappointed and beating myself up over it. I'm wondering if it's the hormones messing with my weight, but I'm hoping it's just temporary and that it'll fall off sometime over the next couple of weeks. the weird thing is, my waistline and hips have stayed the same size over the past 2 months, so I'm thinking its water weight. I don't know what would be going on with me, but suggestions would be helpful!!