Period & nexplanon

Okay so i have nexplanon I started it 3 years ago on June 11th well I just got it replaced this year on June 6th. Well ever since then I had my period before then. Like a week before I put in my nexplanon. Well every since then i haven’t gotten a period or anything. I had cramps a couple days ago & thought I was gonna start cause usually I’ll cramp the day before I start. Well I didn’t. I know I’m not pregnant. But I guess what I’m happening is has this happened to other people. Like I thought it should take at least 3 months of periods when i got it replaced then it stop my period or what not. But for some reason it just completely stopped? Is that okay?