Period tracker

I have my last period logged onto the period tracker on this. I got an implant in about march time and i didnt have a period until the 3rd/4th of last month. It lasted until the 9th and now wen i look at when im due my next one it says the 17th of this month. Is that correct? Because im on holidays then and i dont want to get it. Im unsure if i get a period every month because of this impant and ive only just got one last month. Has anyone had that experience with the implant? And if so do u then get regular periods?