breastfeeding/period cramps x 2 wks but no period

I have been having terrible period type cramps for about 2 weeks but no period yet. My ovaries are hurting (both of them) and my lower back is painful too. I am still breastfeeding my 4 1/2 month old baby and have not had my period yet. Could it be normal to cramp like I am going to have my period for 2 weeks and it never come? Is it hormonal????