I feel exactly the same with my twins! I asked our health visitor about it and she just said not to worry but they are never full! They would just stay in their high chairs and eat all day if we let them.
@N L that's exactly what I thought, as that's what we've been told since day 1. And that's why we just kept giving her food. But she's got a bit chunky 🫣
My little one eats quite a lot (I think) but shes still pretty slim (apart from the baby belly lol) and shes bang on 50th centile, as a guide for example for breakfast she would have one weetabix with warm milk, as well as some fruit, this would be two or three strawberries and a handful of blueberries, or half a banana. For dinner tonight she had half a salmon fillet mashed down a little with 3 ice cream scoops amount (roughly lol) of sweet potato mash. In a day she has 2 x 5-6oz cows milk, breakfast as above, 2 snacks such as greek yoghurt with fruit or rice cakes, a hot lunch such as cottage pie (a weaning bowl sized portion), similar size for dinner, and a small porridge or small pancake for supper. Sorry for the essay but hope that helps, as the others have said I dont think you can really over feed them!
From what I’ve read/been told you can’t over feed them they will just stop when they are full. Personally I’d just carry on as you are but that’s just me