No period after Mirena insertion?

I had Mirena inserted on December 27. It migrated a bit causing non-stop bleeding, for 2 months, until it was removed. Bleeding stopped on Feb 28th. I got it reinserted on March 13th. By now, I thought I would have started my period. I had brown/red spotting on March 20th. It stopped. Then March 22nd and yesterday I had brown spotting/discharge. Nothing today though.

Anyone not get a period after Mirena insertion? Anyone experience brown, sporadic spotting?

TIA