I just found out i'm pregnant and i had been sleeping with a heating pad on my belly several nights. i'm nervous i hurt the baby.

Not a problem: Although heat is considered teratogenic (able to cause birth defects), you would have to raise your core body temperature considerably. A heating pad on your abdomen will not do this. You can continue to safely use it.

Umliky: There is quite a distance and insulation including placental blood flow to protect the fetus.

Possible, not likely: Heat is a known teratogen in the first trimester, however applying a heating pad is not a known cause of concern because the fetus is shielded by your uterus and placenta. Get a detailed ultrasound around 18 weeks to make sure.