35, 20 wks preggo worried advice or stories needed!

My husband and I are currently 20 weeks pregnant I haven’t had the easiest pregnancies can’t say I’ve had the worst either I have a 13 yr old, a 1 year old and this little one is due in July! I have had two miscarriages and one chemical. My husband wants to try for another girl after this little one is around 1/2 years old. I am a tiny girl I’m about 99 lbs and 5ft-5’1. I’m kind of scared to go through another pregnancy even though I do want this. Like am I too old? Is there more complications as you age? Should I just be happy with my 1 girl and 2 boys? It’s just super hard any advice helps or stories. 🤍 thank you