Abnormal vaginal bleeding in between periods?

So I’ve been bleeding to the point of needing a large pad for the past couple days, but I’m not supposed to get my period for another 10 days. I’ve also been cramping for the past week, & today I’ve noticed it hurts on the left side of my pelvic area; especially when bending over to sit. I had an IUD placed in early March & I’m wondering if that has something to do with it, or if this is normal. I had stopped bleeding completely by a couple weeks ago (after my last period), & I had virtually no pain since the implantation; I also rarely cramp around the time of my periods. I know the chances of ectopic pregnancies or an IUD moving are rare, but this pain is making me quite nervous. The bleeding I’m having now is too heavy to be considered just spotting & I don’t usually feel pain or cramping like this; so I’m wondering: should I call the doctor?