SUPER BUMMED !!!

I gave up on the apps for a while it's been 1 year since my Mirena removal and still NO BABY I tried not to stress but I've been trying for a whole year with no I have 3 healthy kids before Mirena all of them back to back and now my man of 3 years wants a baby he's 30 with no children I'm afraid if I can't have another baby he will leave .... I need suggestions ? Is it anything I should be asking the OB/Gyn or any test I should get before completely say I've become infertile ? Please comment