How do you know… babies

I am 32 years old. I have 3 healthy, beautiful kids. 1 girl and 2 boys. My youngest was born in February. I always hoped and thought I would just know when I was done with kids, because honestly I knew it would be a hard for me to admit to myself that I’m done. I can’t help but think maybe I want just one more. 😬 But the thing is, I know we shouldn’t. We’re not old, but we’re definitely not that young either. We don’t have room in our house for another baby. The baby stage is not easy for us either, especially this last one with a 4 and 2 year old to take care of as well. I know deep down we should just be done. But I can’t help but wish I could be pregnant once more. I LOVED being pregnant and my pregnancies and labors went so smoothly. How do you know? How do I decide? My husband said he thinks he’s done but he could probably be convinced.