Am I being selfish? Partner wants another baby.

Ok so we have a 3 month old son right! I waited 5 years for him to be ready to have a child because I love him and he’s worth the wait, but now he wants to have another baby!!!!!! This time I’m not ready for one, I just gave birth 3 months ago for heavens sake and he thinks I’m selfish for saying no. He’s recently stopped using condoms and refusing to pull out, fine but once he stopped I went to the doctors to start the pill because I don’t want another one now. It’s to early and we are new parents, he has this fear of our children having a big age gap, of course I’m not going to wait years to have another but geez give me some time, it just annoys me that I waited so long for him to be ready but I’m the bitch this time even though I’ve gotta carry the baby for 9 months and give birth to the baby and look after the baby plus our son we have now 🤦‍♀️ he doesn’t get it. It’s hard enough with our son now I’m still so new at this and trying to figure it all out I couldn’t imagine what it’ll be like with a second.