Feeling like I haven’t eaten after lunch/dinner

I am noticing that sometimes after my lunch/dinner it feels like I haven’t eaten at all. Like my stomach hasn’t recognised it has been fed. This could last hours or until I eat again. I think it has something to do with the particular mood I’m in. If I am feeling more stressed or something. I cant really figure out what to do. I know the meal is OK as I can eat the same meal at another time and feel satisfied. I am also a slow eater so I dont rush through when stressed. Really interested if you could shed some light on what might be going on here and how I could work with this. Thanks