Pulling sensation

Teri-lyn • 19 F Calgary ab mommy to a three year old minature pincher ttc baby #1 with my bf
 Iam cycle day 5  just finshed my period on the 12 and iam laying in bed with hubby and i get a tight pulling sensation from the edge of my belly button and a tad bit of cramping what on earth is this pain to HPT and it was neg  help ?