I want out

I been in a relationship with this man for three years we are engaged and I did get pregnant once but I miscarried I told him I will like to try again he older and have three kids already but I want more because I have two am I wrong for leaving this relationship because I feel I want more kids and he don’t it’s like one min he do then the next he don’t and today while we both was in the store he goes to get condoms at this point I feel it’s best we both just go on about our way because we not on the same page