After I had my son I got the merina iud I spotted for about a month and since then I haven't gotten my pd or spotting for that matter. Its been 4 months I know I'm not pregnant. Is this normal

I had mirena IUD for four years almost five and only had three periods the whole time. I occasionally had spotting but never more than a few drops. I was told by my ob gyn it was normal but if you are having any other symptoms or think there may be a problem you should go and have it checked