Possible to ovulate while on Mirena??

Sooo I'm a Mirena user, think about 8 months now and yesterday I had some cramping I felt like if I was going to get my period (I do get it monthly but lasts 2 days) then in the evening I went to the bathroom and when I wiped I noticed a ton Egg white cm and today was the same except today it was cloudy and yesterday it was clear!! The same thing actually happened to me last month. I think this is so weird, any Mirena users with same experience?