Implant

So I’ve had the implant for over a year and a couple of months ago my periods have became less and less but I know that is also a side effect. I recently have got into a new relationship and have been having sex a lot and has been finishing in me. I’m a week late for my “period” which has been lessening these past months. But I also did get my 2nd covid jab last month and I know that can have an effect. The implant doesn’t just stop working ?