I feel very sad

I feel very down because my husband and I have been trying to have a baby for the last almost 2 years we have been together I already have a son which he loves him like his own he had his last name before I did 😂😂😂 but I feel our family will be more complete if we had a child of our own.....he feels like he is the problem and I feel like it is me I was diagonsed with PCOS in my teens but my period having been given some medication at the time has been regular ever since idk what to do suggestions anyone