Just a coincidence or is it time to panic?!

I have an the IUD(Skyla) for exactly a year now. I have spotted(instead of a regular period) every month since I had it put in. Just within the last couple of months(starting in November) I had stopped spotting what so ever. I had recently got a new boyfriend, which was in September. So I thought maybe there a chance I was pregnant. So I took 2 test, both blue and pink dye. They were both negative. Could it be just a coincidence that I randomly stop spotting all together? Is that normal? Common? Just a little stressed over here 😩😩