I want more babies but definitely do not need anymore right now

So I am a single mother of two children and I love being a mother but I am also a struggling college student trying to make it in this world. Anyway, so I have been with my boyfriend for a little over a year now and lately baby talk has been coming up way too often. My boyfriend and I know we want to have more children but we both know now is not the time, but now my oldest daughter (she is three) has been asking for a brudder (brother) and I work with children and I see all of the little babies and it makes it so much harder not to want more. I want to focus on school and get my career started but I want to continue to grow my family. I just need some positive words of encouragement... someone please help Suppress my BABY FEVER! 🙅🏽👶🏽