Decisions about trying for another child

I’m 42 and have a 3.5 yr old son. Before him I miscarried at 11 weeks and I’ve also had 2 miscarriages since him- we were actively trying. It’s been about a year since my last miscarriage and they have now found out I have a syndrome which is something I can take meds for before trying again -which may possibly help me next time round which in theory makes the idea less scary.
I am currently however not trying and the thought of it doesn’t sit well with me and can get myself in a really anxious state about what to do as time is running out due to my age.
My gut tells me I’m very fulfilled with my son and I feel very grateful to have him and feel so happy he is in my life. Having just one then also allows me to focus on myself in terms of my job which I love (I run my own business as an illustrator) and also allows me to have time to look after my mental health with tools such as yoga, swimming, gardening which has greatly suffered over the years (I think I may have GAD and I also possible have PMDD and since my son was born I have struggled even more)
Some of my close friends have just had their second babies and I wonder if I’ll regret the decision once it’s too late. I also feel very responsible I am making a decision that also affects my son and my partner and I am constantly analysing what is the right thing to do.
I also am trying to work out am I just scared of having another miscarriage? (a very traumatic experience which definitely tipped me into a period of awful anxiety) and maybe I just can’t face this part of it again and I am convincing myself I don’t want to try. Or is it because I know my limits and 1 child seems so much more do-able for me and I can really focus on him and give him the best version of me whilst giving myself time for other things that give me joy. But will I wish I had tried to have another after the initial tough period of the first few years it would be amazing to have a sibling for him. I still come back to how my partner and my son will feel in 10 years time about the too.
I know you can’t tell me whether to try to have another child or not- no one can and I know this has to come from me, but I guess you may be able to help me see more clearly about my worries. I want to move forward with this but there is a part of me that also knows maybe there will never be an answer I am truly happy about and I have to learn to live with this.
My Model I have tried:
C;I have 1 child
T; I’m going to disappoint him
F; Shame
A; ruminate, have obtrusive thoughts, question everything, catastrophes, procrastinate on what to do
R;Imagine my life not being as I imagined . I’m living in limbo and not being present
Many thanks in advance, warm wishes

 

Answer:

You are bringing some great awareness to the table. Let see if we can slow things down a bit. Your model is pretty clean…nice work. 
What if there is no right or wrong decision for you or your family, just two options – each with their individual pros and cons? It’s okay to feel and think what you are feeling and thinking, but when our T’s and Fs are laced with shame, we tend not to create Rs that we like.
Can you imagine feeling compassion for yourself right now in this situation? If you can, what Ts create that feeling for you? If it’s hard to figure this out for yourself, think about what Ts you would offer to someone else in the same situation. 
What happens or changes for you when you feel compassion instead of shame? Try putting compassion in the F line of your model and come back to us with your discoveries and questions.
C: Have 1 son, and was told that there may be another opportunity to have another by doctors.
T:
F: Compassion
A:
R: