Belly pain

Ok so I'm 35 years old. This is second pregnancy and I'm 27w3d. So the last couple of days I have been experiencing so very sharp pain on my belly. And in my belly button. It's not Braxton hicks I know that because I've been having those for bout a month now and this is different kind of pain. Baby is moving and kicking jus fine. Could it be muscle skeletal pain? Or jus my skin stretching? Or something else? Don't really know. Is anyone else experiencing this? Also would it be ok to use a heating pad on my belly to help the pain?