Sometimes it is absolutely normal- In otherwords, just because the bleeding has stopped it does not necessarily mean you are done:
What age were you when you stopped bleeding?

For me I went a year without bleeding then bamm
I had a period 1 year later-
Funny but I had gotten involved with a man at the time

And while I was not sleeping with him- I did have sexual thoughts and I think I "thunk" my estrogen up- and then the cycle started
There was no other eason with me either??
So go figure...
The process can take 10 years