Periods on Nexplanon

So I got the Nexplanon implant a little over a month ago. I was tracking my periods regularly and before the implant they were always on time. But now that I have the implant I have yet to have a period. Has anyone else experienced this? Most people I talked to say that they have more bleeding and spotting than usual or like nonstop periods for a long time. I would just hate to be blindsided by pregnancy.