Trying to conceive

Just venting!!! I have two children ages eleven and eight. I had them early. I was a teen mom and now that I'm actually 28 married financially stable I cannot seem to get pregnant!!! It's so frustrating. I want a baby with my husband then plan on getting my tubes tied. I literally cry every time I get my period. I have sex when ovulating and when I'm not. We have a great sex life. He has a daughter from a previous so I know we both can reproduce. Making an appt with on to see what else I can do been trying for a year and nothing its so depressing!! Then u see all these women and junkies getting pregnant or women that don't even deserve to have children it's killing me!!!!