What age do babies "forget" what its like in the womb? Im asking cuz my son is 6 months and today i…

What age do babies "forget" what its like in the womb? Im asking cuz my son is 6 months and today i layed him on his back in the tub. (It was shallow water and i was in the tub with him) and he got real calm and still and just looked at me. I know it sounds silly but it Kinda reminded me of him in the womb. I was jus curious if he maybe felt like he was back in there.