Car seat cries

Our 5 month old has been crying when we take her OUT of her car seat. Then I give her boob and she’s fine but I don’t known why she’s crying. She’ll cry in the car sometimes and that’s normal. Then when we park and take her out of the car (still in her car seat) she’s fine because she sees us and is distracted by the world. So she’s not crying. We get inside, she’s not crying. I wash my hands she’s fine, but as soon as dad or me picks her up she cries. I don’t know if her legs fell asleep? If her back hurts from sitting in the seat? Or something else? I’m just curious if this has happened to anyone else? We took her car seat cushion out about a month ago because we had to adjust/move the straps to the next hole on the car seat and the cushion no longer fits because there isn’t another hole for the strap. So I’m wondering if there isn’t enough cushion? But then I think she’s just telling us that she’s hungry because I feed her and she usually stops right away. 🤷🏽‍♀️