Indentation in belly

So I’m 3 Months pregnant and sometimes my belly hurts (I’m assuming from gas since after I “relieve” myself it stops hurting) and when it does I rub the top. Well today I was rubbing it and felt like an indentation or division smack in the middle of my stomach. It starts around my diaphragm and extends about 5 inches. I’ve tried looking it up online to see since I don’t see my dr for a few weeks but every question and answer is associated with pain and I’m not having pain. Anyone have any ideas?