What am i doing wrong?

Red • TTC 10 months
I know theres lots of topics on this already but whens it my turn?
​3 of my friends are pregnant all within a few weeks of each other, all very different lifestyles, ages and esp sizes... What am i doing wrong?
​I've been using glow for 5 months TTC for 10, i've lost 5 stone and excersise got a better job and own my own place..  I'm taking vitamins too
​We definitely do things on the right dates but still nothing, feel like i'm failing at something i should naturally be good at!
​Is there anything i can try ? Or am i just getting baby envy :-/