I get it too Em. Took us 2 years to get pregnant the first time and the second year of that was hard as I was starting to give up hope. Happened naturally in the end, if you take ovulation sticks into account!
This summer I felt like you do now when i heard SIL was pregnant. We had been trying for DC2 for a year (and that's with ovulation sticks!) so again I was giving up hope. I suppose I also felt sad for DS because I expect they will have a 'perfect' child and I know MIL struggles with DS's ASD (whilst also not acknowledging it
). Anyway, 2 days later I found out I was pregnant ... and then I lost it. I was dreading SIL having the baby in the NewYear as I knew I would be thinking about my lost child but after all previous slow efforts we got pregnant again within 3 months. Hopefully all will be well this time.
(still feel a bit sad for DS but we, and my family, adore him Even though he has been a little beast today ).
Anyway Em you have no reason to fret yet but if you are feeling like that about it then worth maybe getting serious. I do recommend peeing on sticks as Mummy says. Most likely you won't have any trouble but if you do you still have lots of time. I wish we'd started earlier, I started ttc around my 35th birthday and I will be 42 when I have this second one (all being well).