Need advice plz help

I had the Mirena put in I believe July it was I had it removed in January like the 6th due to having problems and I turned around had a period on the 8th for about 4 days and the ln didn't have a period until February 21st but I spotted on then it lasted till the 25th but spotted off so I have been cramping and moody sleepy dizziness and tired but still haven't had a period but every test I take has been negative except 2 was faint positive... is this the iud or what and could my cycles be a 35 range I am not sure now plz help