Struggling to conceive number two - finding no1s behaviour difficult

[Marshnic]

We've been off birth control since last April and no sign of pregnancy so far. My daughter is three and the only thing factor that I can see is different this time round is dealing with my daughter's behaviour. I find her very stressful and after speaking to my doctor a few months back she highlighted this could be affecting our chances and that my body is basically telling me I'm not ready for another child yet. Surely plenty other parents go onto conceive when their child is 2/3 years old. Between my daughters behaviour and my lack of conception I can't see a light at the end of the tunnel. Does stress really affect things?

We have also been ttc #2 since last April. DS is almost 2
I have also been told by GP that stress might be a factor but in my case it's my job that causes the most stress.
I did conceive in November (ended in mc) and I was at my most relaxed that month so maybe there is something in it?

I'm sorry to hear of your miscarriage. I get myself caught in a loop, the minute I feel I'm struggling with my daughter I get worked up because I know it will affect our chances to conceive. How can you destress with a threenager!?