Only had Nexplanon for 4 months and nervous

I know the most common symptom of Nexplanon is irregular bleeding. I haven't had a period since the week after having it put in, which was about 4 months ago.

Realistically I didn't have sex until over a month after having it put in, and I use condoms. (The first time was pull out which I know is not smart but doctor said Nexplanon is most effective)

But I'm still like

I've never skipped a period before so I'm wildin