Mirena IUD - signs it's running out early?

Hello,

I have had my Mirena IUD since December 2017. After the first few months I was one of the lucky people who completely stopped getting their period. It was great!

About 6-8 months ago I have noticed my periods coming back full swing, crazy cramps, acne, hair thinning, etc.

Has anyone experienced their Mirena running out of hormones early? Does that sound like it might be? My doctor is very dismissive about my concerns and basically thinks it's impossible. But my body is acting like it is gone (it's not, feel the strings).

I have a lot of monogamous sex with my boyfriend and my only protection is just my IUD, so I'm kind of concerned about this 😅.

Has anyone else dealt with this ?