Give me your thoughts please.

So I’ve had my iud (Mirena) for about a year, almost 2 years. I have an 18 month old son who I love but I really don’t want anymore kids (I’m 18). So I stopped bleeding from getting my Mirena in November of 2016 but I got my period again October 2017 right after having sex for about a year. But in November of 2017 I thought I would get my period again and I didn’t so I went to the doctor and they said I was not pregnant (thank god) so we fooled around maybe like 2 other times in the month (he pulled out). I got my period in December again for 5 days and it’s February and I still haven’t gotten my period again. But keep in note we didn’t do anything in December since he left to another country. But I haven’t gotten my period for two months now and I’m not throwing up or anything, I’m in my same weight as always and my breast are fine but I just don’t get why I haven’t gotten my period again. I plan to go see my doctor soon but im not sure when I’ll get time. Let me know if you’ve had this happen to you too with Mirena.