My man and me have been together for a year and for the past 6months we have been TTC. He already has 2 kids with his ex so he def can have kids. He cums inside of me and we try different positions. He waits a minute inside of me to see if that helps us get pregnant. He thinks im the one that cant have kids. He thinks that bcus Im young and never been pregnant. Any advice or suggestions  on what to do