Probably not. It is normal for your period to be "gone" for awhile, especially if you are breastfeeding. My period still hasn't returned to normal, I used to be very regular, My baby is 2 1/2 and I still get irregular periods, never have gotten back to normal. Probably wouldn't hurt to call your doctor, but I wouldn't be worried if I was you. Hope it works out for the best.
After I had my 1st child I didn't get my period for 3 months. I finally called the doctor and she prescribed something to bring on my period. And just about a week or so after that it was here.
Lisa