Am I having a miscarriage?

I have the nexplanon implant, I’ve had it for almost 2 years and before this one I had another one for almost 3. My period schedule have always been irregular on it but the periods themselves have always been normal. Light/medium bleeding the first day, heavy on day 2 and 3, and progressively gets lighter until day 7 when it stops. But this period is different I’ve been heavy bleeding and then nothing, I think I stopped, and then a day later heavy bleeding and then stops for a day and so on. I’ve never had a period like this and to top it off on the heavy days there’s a LOT of thick blood clots. Huge ones, and I rarely get them in my normal periods. But I’m not cramping at all, and I’ve always heard that you cramp a lot when you miscarry. Does anyone have any ideas what’s going on? I’m kinda scared tbh